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अब Quizwiz के साथ अपने होमवर्क और परीक्षाओं को एस करें!

Treatment: How do you treat an actinomycosis infection?

According to Oppenheimer (1978): - Surgical excision with long-term Abx therapy (one month) According to Sundqvist (1980): - There might be no need for prolonged Abx if the periapical infection can be surgically removed. According to *Rush*: - 86% healed w/o Abx - 100% healed w/ short-term Abx - 25% healed w/ long-term Abx Abx therapy does not appear to be necessary after surgical enucleation

Pathogenesis: How does actinomycosis typically present?

According to Oppenheimer (1978): This infection classically presents as a "brawny, submandibular swelling which, if untreated, discharges through multiple sinuses."

Prognosis: What is the success rate for apexification of immature teeth with MTA?

According to Pace: 94% at 10 years

Application of Biologic Principles: How do benzodiazapenes work?

According to Page: The bind to the GABA channels, thus inhibiting brain synapses and leading to sedation and amnesia.

Application of Biologic Principles: In general, how should antibiotics be prescribed?

According to Pallasch: 1. Rx for the shortest duration possible to reduce risk of toxicity and allergy, but long enough so that host defenses can return to fight the infection 2. Doses that are high enough to reach MIC (minimum inhibitory concentration), given in intervals of 3-4x the half-life of the drug. 3. Consider a loading dose of 2x the maintenance dose to reach the appropriate serum concentration faster.

Anatomy: what types of collagen can be found in the pulp?

According to Pashley, The pulp is rather odd when it comes to collagen...it contains Types I, III, and V. Type III Collagen is the most predominant (43%)

Medical History: What patients is it inadvisable to prescribe dexamethasone to?

According to Patten et al (1992) -Pregnancy -gastric ulcers -hypertension -diabetes -active infections

Biologic Principles: Pain associated with RCT is believed to be the result of a combination of what factors?

According to Patten et al (1992) 1. Periapical inflammation caused by overinstrumentation. 2. Irrigating Solutions 3. Pulpal Breakdown Products

Biologic Principles: What is the effect of prolonged use of cortisol or dexamethasone?

According to Patten et al (1992), It will suppress the endogenous secretion of cortisol (adrenal suppression). Short term use of the corticosteroids have shown essentially no side-effects.

Biologic Principles: How do steroids differ from NSAIDS?

According to Patten et al (1992): NSAIDS reduce the amount of prostaglandins only, whereas steroids are also effective against leukotrienes and bradykinin

Treatment: What is the use of calcium sulfate in surgical endodontics?

According to Pecora (2001): -propping up the gingival tissue -prevention of scar formation -improved clinical outcome *Note: calcium sulfate is exothermic, so use caution when near the sinus membane. It shouldn't de-vitalize teeth.*

Prognosis: What is the effect of a positive or negative culture on the outcome of endodontic treatment?

According to Peters as well as Molander: none.

Objective Examination: How effective are cold, heat and EPT tests?

According to Petersson (1999): Cold Testing: Sensitivity: 0.83 (83% of pulp necrosis - disease - was positively identified) Specificity: 0.93 (93% of vital teeth-lack of disease- were positively identified) Overall accuracy of cold testing is 86% Heat Testing: Sensitivity: 0.86 Specificity: 0.41 Overall Accuracy: 71% EPT: Sensitivity: 0.72 Specificity: 0.93 Overall Accuracy: 81%

Prognosis: What is the effect of endodontic access, endodontic procedures, and restorative procedures on tooth stiffness?

According to Reeh and Messer: Endodontic procedures themselves did not produce substantial effects relative to tooth stiffness. 5% reduction from the endo access 20% reduction from occlusal preparations 46% reduction when one marginal ridge is involved. 63% reduction when an MOD preparation is involved.

Pathogenesis: What is the relationship between bacterial penetration and pulpal pathosis in carious teeth?

According to Reeves & Stanley (1966): -No significant inflammatory response is seen until the microorganisms get within 0.5 mm of the pulp. -Inflammation of consequence, (i.e. probably irreversible) was only seen after frank invasion of the reparative dentin.

Radiographic Examination: How much bone destruction must you have before it becomes evident on a radiograph?

According to Seltzer & Bender (1961): The cortical plate must be breached before the lesion will be demonstrated on a radiograph. PS. The palatal root is a long ways away from the buccal cortical plate, so you could be missing a lot. - you can have an extensive lesion that is not apparent radiographically if it never breaks the cortex. - another reason to get a cone beam.

Diagnosis: What is the correlation between clinical diagnostic data and actual histological findings?

According to Seltzer & Bender (1963): The clinical data does not always line up with histological findings. Langeland supports this as well.

Complications of Treatment: What is the major concern of accessing through a crown with respect to the integrity of the crown? What concerns do you have about placing a resin core?

According to Schwartz: Access openings through a crown reduce the retention of the crown. Resin cores show high levels of leakage due to polymerization. Recommendation: bulk fill with RMGI, then place two increments of composite over the top.

Treatment: Do you leave an abscessed tooth open for drainage, or do you close it?

According to *August*, close it up (more hygienic). Only 5% of these cases have flare-ups (compare to *Walton*'s 3% flare-up rate overall for all endodontic teeth).

Radiographic Interpretation: What is the position of the mental foramen relative to the apex of the second premolar?

According to *Phillips and Weller*: an average of 3.8mm mesial and 3.5mm apical to the apex.

Prognosis: How effective is internal bleaching with a tetracycline-stained tooth?

According to Abou-Rass: intentional root canal treatment and internal bleaching is very effective in anterior teeth.

Pathogenesis: What happens with regards to external inflammatory root resorption when it includes less than 20% of the root surface, and more than 20% of the root surface?

According to Andreasen and Kristerson: <20%: reversal of resorption may occur, and ankylosis may be prevented. 20+%: progressive replacement resorption is inevitable.

Trauma: what traumatic dental events need to be addressed immediately (within hours)?

According to Andreasen: Acute Priority Injuries: - Root Fractures - Alveolar Fractures - Lateral Luxation - Extrusive Luxation - Avulsion

Complications of Treatment: What are the incidences of Pulp Necrosis associated with the various forms of tooth trauma?

According to Andreasen: Concussion: 3% Necrosis Subluxation: 6% Extrusion: 26% Lateral Luxation: 58% Intrusion: 85% Prognosis is worse with increased age, completed root formation, and extent of injury

Trauma: what traumatic dental events can be addressed in 24+ hours?

According to Andreasen: Delayed Priority Injuries: - Uncomplicated Crown Fractures

Trauma: what traumatic dental events need to be addressed within several hours (as opposed to within a few hours/immediately)?

According to Andreasen: Subacute Priority Injuries: - Complicated crown fractures - Concussions - Subluxations - Intrusions

Prognosis: Discuss the success of endodontic success rates of teeth restored with crowns, particularly the second molars.

According to Aquilino: 2nd molars were 5x less likely to succeed than all other teeth combined.

Complications of Treatment: which patient population is more at risk for BRONJ, the oral bisphosphontes, or the IV bisphosphonates?

According to Assael: The IV Bisphosphonate patient population.

Complications of Treatment: at what point post-trauma can vitality testing be more predictable of the actual state of the pulp?

According to Barkin: 3 months. However, if a tooth tests vital immediately post-trauma, it is a good prognosticator that it will remain vital (Zadik). Teeth that do not regain positive responses within 6 months will require RCT.

Treatment: You are NOT a fan of pulp capping. Who can you cite to support your position?

According to Barthel (2000): Retrospective study following 5-10 year outcomes of teeth that were cariously involved and pulp capped (the primary reason that pulp caps are done). Results indicated that direct pulp capping should be avoided. DPC may be an option if you're trying to prolong the longevity of the tooth for no more than 5 years.

Prognosis: What are the success rates for pulpotomies?

According to Barthel: - 45% Necrosis after 5 years (55% success) - 80% Necrosis after 10 years (20% success) According to Mente: - Long-term success w/ CH: 58% - Long-term success w/ MTA: 80%

Complications of Treatment: How thick is the smear layer, typically?

According to Baumgartner (1984): 1-2µm thick

Treatment: You are about to use ultrasonics for your surgical root-end preparation. Will you use high-frequency or low-frequency?

According to Baumgartner (1996): the use of low-frequency ultrasonics results in significantly fewer numbers of cracks in the tooth.

Treatment: What's better for apical surgery, high-speed bur or ultrasonic tip?

According to Baumgartner (1997): Ultrasonic root-end preparations were superior overall to high-speed bur root-end preparations due to reduced bevel angles, depth of preparation with minimal deviation from original canal space, and decreased bony crypts required for access.

Application of Biologic Principles: How well do the common antibiotics work against bacteria associated with endodontic abscesses?

According to Baumgartner (2003): Susceptibility of bacteria were at the following percentages: - Metronidazole: 45% - Pencillin V: 85% - Amoxicillin: 91% - Clindamycin: 96% - Augmentin: 100%

What is the down-side to mixing EDTA and NaOCl?

According to Baumgartner, it reduces the effectiveness of the NaOCl.

Biologic Principles: How effective are antibiotics at fighting abscesses of endodontic origin?

According to Baumgartner, the 98 strains of bacteria isolated from 12 different abscesses are as follows: 1. Augmentin (Amox + Clavulanic Acid): 100% 2. Clindamycin: 96% 3. Amoxicillin: 91% 4. Penicillin V: 85% 5. Clarithromycin: 78-89% 6. Metronidazole: 45% Metronidazole by itself doesn't work too well, but it can be combined with either Pen VK or Amox, and it will boost their efficacy.

Pathogenesis: Describe the bacteria flora from carious lesion to periapical granuloma.

According to Baumgartner: 68% of the bacteria harvested from the apical 5mm of an infected tooth was anaerobic. As bacteria penetrate apically in necrotic root canals, anaerobic succession apparently occurs because of the compromised blood supply, the lower oxidation-reduction potential in the necrotic tissue, and the establishment of synergistic relationships with other bacteria. In other words: The oral cavity is well oxygenated, therefore at the surface of a carious lesion, you would expect to find strict/facultative aerobes. As the lesion progresses through the dentin and into now-necrotic pulp tissue, the environment changes from aerobic to anaerobic. Thus, you would expect to find less aerobes, and more facultative/strict anaerobes. At the end of the root canal space and into the granulation tissue, the oxygen content is very poor, and as Baumgartner found, you would expect to find predominantly strict anaerobes.

Treatment: how long will it take for microleakage to occur with either a RMGI or MTA provisional restoration?

According to Baumgartner: 50 days on average.

Pathogenesis: Where does the sinus tract epithelium originate?

According to Baumgartner: at the mucosal surface (not from the PA lesion).

Pathogenesis: Describe the following: Ortho extrusion+ Perio = Endo

According to Bauss et al (2010), teeth that have a history of severe periodontal injury have a higher susceptibility to pulp necrosis during orthodontic extrusion. Severe periodontal injury may cause permanent damage and/or reduction of apical vessels, which may account for this increased likelihood of necrosis.

Radiographic Interpretation: What percentage of bone mineral loss must occur before a lesion is present radiographically?

According to Bender (1982), 7.1% mineral loss (on the endosteal side) is needed. Additionally, the angle with which the radiograph is taken will have an effect (so always take multiple angles).

Radiographic Examination: How much mineral bone loss must there be for a lesion to be detected radiographically?

According to Bender (1982): 7.1% mineral loss on the endosteal side. Remember: 25:1 ratio of minerals between cortical bone and cancellous bone.

Complications of Treatment: What percentage of teeth with PFMs alone or as and FPD abutment are going to need Endo?

According to Cheung: PFM failure post cementation was 16% FPD abutments post cementation was 33% Average follow-up for this study was 14-15 years.

Root Canal Anatomy: What direction will the apex of a maxillary lateral incisor dilacerate?

According to Chohayeb (1983): Summary: -Distolabial dilaceration was present in 52% of maxillay lateral incisors studied. -More than 70% dilacerated to the labial in some form. Key Point: look at how your initial K-file presents upon removal from the virgin canal. This will give you a clue as to the direction of the dilaceration.

Prognosis: What's more important with regards to the success of your endodontic treatment: what you take out of the canal, or what you put into it?

According to Chong & Pitt Ford (1992): What you take out is more important than what you put in. Don't use this as an excuse to do bad work though...

Treatment: By binding your irrigation tip in the canal, you can force more irrigant apically. Is this a good idea?

According to Chow (1983): No. It's not a good idea. The author advocates placing the tip of the irrigation needle as close to the apex as possible without binding.

Application of Biologic Principles: should antibiotics be a first line treatment for an endodontic infection?

According to Goldstein, no (except in the case of acute osteomyelitis or cellulitis, or significantly immunocompromised patients). A pulpless tooth has all the conditions that favor the survival and emergence of a bacterial resistant bacterial population. - Poor diffusion properties of necrotic tissue create an acidic environment for the bacteria to thrive in. - Microbes are at a low level of activity, and thus can withstand long exposures to high concentrations of antibiotics. - Pus and necrotic tissue readily absorb the Abx, making it difficult to attain adequate levels - Fibrin clots and abscess walls are avascular, limiting the distribution of the Abx

Treatment: What would a good intracanal medicament be for eradicating E. Faecalis?

According to Gomes & Sousa (2006): 2% CHX gel is effective against E. Faecalis. Note: combining CHX with Calcium hydroxide may inhibit the effects of CHX on E. Faecalis.

Prognosis: What tooth has a better chance at survival, overfilled or underfilled?

According to Grahnen and Hansson (1961): Teeth overinstrumented and overfilled failed more than underfilled teeth.

Treatment: What is the best way to stabilize a crack?

According to Guthrie, crown it. Adjusting the occlusion, placing a direct restoration, or banding the tooth does not protect the tooth from pressure produced interocclusally with a food bolus. Full-coverage crowns do.

Application of Biologic Principles: describe the interaction between NSAIDS and methotrexate (for cancer and rheumatoid arthritis).

According to Haas: Okay to combine when treating for RA, but when higher doses are given (cancer patients), NSAIDs should be avoided.

Treatment: How do you feel about using 4% Articaine for an IAN block?

According to Haas: 5x increase in parasthesias when 4% Articaine is used. Garisto reports a 7% increase with the use of 4% Prilocaine.

Treatment: What should you do if a patient is in active orthodontic treatment, and you find a necrotic pulp?

According to Hamilton (1999), Treat the pulp with calcium hydroxide, and complete the obturation after the ortho is completed.

Treatment: T/F: Endodontically treated teeth can be orthodontically moved as readily as teeth with vital pulps.

According to Hamilton et al (1999) True.

Etiology: how does the bacterial flora differ from a primary endodontic infection to a secondary endodontic infection?

According to Hancock and Trope (2001): The microbial flora was mainly of 1-2 strains of predominantly gram-positive organisms. Enterococcus faecalis was the most commonly recovered bacterial species.

Pathogenesis: What are the characteristic features of an actinomycosis infection?

According to Happonen (1986): - persistent infections (ie. tooth has been treated, but the lesion persists or gets larger) with several exacerbations - multiple sinus tracts, typically on the facial (sinus tracts on the facial and lingual are more indicative of a fracture) -Radiographically consistent with those of inflammatory periapical lesions - no specific features -perforation of the buccal and/or palatal cortical plate -yellowish/grayish granules within the granulation tissue

Radiographic Interpretation: You want to look at the roots of the maxillary molars, but the zygomatic arch is in the way. in what direction do you shift your cone?

According to Goerig: take a disto-angled shot. This will move the zygomatic arch mesially, and expose the root apices.

Radiographic Examination: How reliable are radiographic interpretations?

According to Goldman, there is only a 46% inter-examiner reliability between two different examiners, and only a 70% intra-reliability with the same examiner looking twice.

Treatment: What injection technique works better, Gow-gates or standard Inferior Alveolar?

According to Goldman: there's no difference. According to Malamed: Gow-Gates is superior. According to Reader: the success rates of a standard IAN block range between 15%-57%. Therefore, supplementing it is a good idea.

Application of Biologic Principles: What are "The Three Ds" for pain control, as described by Hargreaves?

According to Hargreaves, effective pain control of odontogenic origin is: Diagnosis Definitive Dental Treatment Drugs

Application of Biologic Principles: list 7 possible causes for anesthetic failure.

According to Hargreaves: 1. Anatomic failure 2. Acute tachyphlaxis 3. Inflammatory effects on local tissue pH 4. Inflammatory effects on blood flow 5. Inflammatory effects on nociceptors (sensitization and sprouting) 6. Central sensitization 7. Psychological factors

Complications of Treatment: What are the commonly cited reasons for anesthetic failure in dentistry?

According to Hargreaves: 1. Lower pH of inflamed tissues. 2. Unsuccessful techniques. 3. Altered resting potential in inflamed nerves. 4. Upregulation of anesthetic-resistant sodium. 5. Patient Anxiety.

Application of Biologic Principles: What is the maximum dose of Lidocaine that can be administered?

According to Hargreaves: 350mg of 5.0mg/kg (9 cartridges)

Application of Biologic Principles: What is the maximum dose of Marcaine that can be administered?

According to Hargreaves: 90mg or 1.25mg/kg (about 10 cartridges)

Application of Biologic Principles: What receptors do narcotics typically act on?

According to Hargreaves: Central µ and κ receptors. They are advocated only in the treatment of severe odontogenic pain.

Application of Biologic Principles: What is the mechanism of action for Ibuprofen?

According to Hargreaves: Ibuprofen blocks the Cyclooxygenase 1 and 2 enzymes, thus preventing the production of prostaglandins.

Application of Biologic Principles: T/F - the combination of tramadol and NSAID provides superior short-term relief than either drug alone.

According to Hargreaves: True.

Application of Biologic Principles: Describe the timeline and series for healing following endodontic surgical intervention.

According to Harrison & Jurosky (1991): Day 1: Blood Clot, lots of PMNs (inflammation), periosteal necrosis, and a thin epithelial seal. Day 2: Multilayered epithelial seal; Macrophages become the predominant inflammatory cell; Type III Collagen production Day 4: Blood clot is replaced by granulation tissue; Type 1 Collagen production; Osteocyte proliferation from the endosteum Day 14: Normal sulcular epithelium; woven bony trabeculae occupy the wound; new periosteum evident Day 28: Maturing bony trabeculae occupy the wound.

Treatment: You just resected a root apex. Do you demineralize it, or not? Justify your answer.

According to Harrison (1993): - Improved healing and cementogenesis was noted after removal of the smear layer and exposure of organic tooth structure. According to Torabinejad (1997): - Demineralizing the root end prevented cementogenesis over the MTA plug.

Application of Biologic Principles: What is the difference between Dentoalveolar healing and Osseous Healing?

According to Harrison (1997): The Short Version: - Dentoalveolar Healing: the apical attachment apparatus is reformed. - Osseous (ie. Alveolar) Healing: cortical and cancellous bone is reformed. The more detailed version: Dentoalveolar healing results in the reformation of an apical attachment apparatus associated with the resected root surface. The tissue responsible for dentoalveolar healing is the root-end encapsulating tissue, which proliferates from the severed PDL following root-end resection. As a product of the PDL, this tissue contains cells with the genetic capability of forming the tissues necessary for an attachment apparatus, that is, cementum, alveolar bone proper (tooth socket), and collagen fibers. The re-formed attachment apparatus is composed of functionally oriented PDL fibers (Sharpey's fibers) attached to new cementum deposited on the resected root surface; these connect to new alveolar bone proper deposited subjacent to the resected root and the root-end encapsulating tissue. Osseous healing (alveolar healing) ideally results in reformation of cancellous and cortical bone, which were either removed during surgical entry to gain access to the root or destroyed by periradicular pathosis. The tissue responsible for osseous healing is endosteal tissue proliferating from the severed endosteal tissues associated with trabecular bone on the periphery (wound edges) of the excisional wound. This tissue contains cells with the genetic capability of forming new bone (woven bone). The bone deposition progresses from the internal wound edges to the cortical (external surface).

Application of Biologic Principles: What are the primary reasons for prescribing an antibiotic in the treatment of endodontic disease?

According to Harrison and Svec (1998): 1. Infections with rapidly increasing signs/symptoms. 2. Evidence of Systemic Involvement 3. Immunocompromised Patients 4. Involvement of Anatomical Danger Zones According to the AAE (2012): 5. Fever greater than 100°F 6. Lymphadenopathy 7. Trismus 8. Osteomyelitis 9. Persistent infections

Application of Biologic Principles: In what cases are antibiotics contraindicated?

According to Harrison and Svec: 1. Irreversible Pulpitis 2. Asymptomatic Radiolucency 3. Sinus Tracts 4. Fluctuant Swelling 5. Pain but no symptoms of infection

Pathogenesis: What are sinus tracts lined with?

According to Harrison: either epithelium or granulation tissue containing chronic inflammatory cells. *According to Baumgartner:* - 33% had epithelium (either complete or interrupted)

Application of Biologic Principles: does calcium hydroxide dissolve necrotic tissue?

According to Hasselgren (1988): Over a long period of time, yes, but it must be in contact with the tissue.

Application of Biologic Principles: Why do you use Calcium Hydroxide? What does it do for you?

According to Heithersay (1975): The Ca(OH)2 paste is used in situations where hard tissue formation is required. The author outlines 11 of these clinical situations: 1) Control of periapical exudation, 2) Temporary root filling in teeth with large periapical lesion; 3) Dressing agent in routine endodontic therapy; 4) Temporary root filling where time does not permit the completion of normal endodontic treatment; 5) Control of apical resorption resulting from periapical pathology; 6) External inflammatory resorption due to trauma (i.e. luxation or following replantation); 7) Control of internal resorption in the apical region; 8) Control of internal/external resorptive defects; 9) Management of perforations; 10) Treatment of the transverse root fractures (in particular where resorption has occurred between the fractured segments or within the root canal); and 11) Apex formation in pulpless incompletely developed teeth.

Complications of Treatment: what is the incidence of invasive cervical resorption in teeth that have been internally bleached?

According to Heithersay: 1.96% in teeth with no barriers placed.

Application of Biologic Principles: Describe the interactions between the following: Broad spectrum Abx (PCNs/Tetracycline) and oral anticoagulants. Benzodiazapenes and macrolide Abx Abx and oral contraceptives

According to Hersh (1999): - Tetracyclines or other broad-spectrum antibiotics with oral anticoagulants can reduce endogenous vitamin K levels and enhance the effects of oral anticoagulants by decimating the normal gut flora that produce vitamin K; monitor patients for signs of increased anticoagulant activity - bruising, bleeding. - Midazolam or triazolam with macrolide antibiotics (Zithromax, azithromycin, erythromycin group) or azole antifungal drugs: oversedation with prolonged and intense psychomotor impairment is a likely outcome, though the authors admit that the large therapeutic range for benzodiazepines yield no strict toxicity. - Rifampin (Rx'ed for TB) is the only antibiotic that has been scientifically demonstrated to interfere with the effectiveness of oral contraceptives; however, enough precedence has been set in court that says otherwise; would still be wise to inform/warn patients for legal purposes.

Application of Biologic Principles: What are the three structural parts of all injectable local anesthetics?

According to Hersh: 1. Aromatic/Lipophilic Portion: penetrating lipid-rich nerves. 2. Amino Terminus: confers water solubility (to keep it viable in the cartridge) 3. Intermediate chain: separates the anesthetic into two categories: esters and amides

Application of Biologic Principles: What are the three primary actions of local anesthetics?

According to Hersh: 1. a reduction in the permeability of the nerve cell membrane to sodium ions 2. a decrease rate of rise of the depolarization phase of the action potential. 3. A failure of a propagated action potential to develop

Application of Biologic Principles: What is Phentolamine mesylate, is it safe, and what dental population is it recommended for?

According to Hersh: Phentolamine mesylate is used to reverse the effects of local anesthetic. It is safe to use, and is most recommended for pediatric patients.

Application of Biologic Principles: what is the pKa range for common dental anesthetics?

According to Hersh: dental anesthetics are weak bases, with pKa ranges from 7.6 (Mepivicaine) to 8.9 (Bupivicaine)

Complications of Treatment: What is the pH environment of an acute infection, and what is the resultant complication on anesthetic?

According to Hersh: The pH at the injection site in an acute abscess can approach 4.0, resulting in more than 99% of the anesthetic molecule remaining in the cationic (impermeable) form

Treatment: You decide to pulp cap. What material will you use, Calcium hydroxide or MTA?

According to Holland (2001): MTA performed significantly better than DyCal.

Prognosis: How successful is internal bleaching?

According to Howell: Color regression took place in about 50% of the teeth and there was a tendency for teeth which took longer to bleach to be more likely to discolor again. Feiglin did a 6-year study and found that younger teeth are ideal for internal bleaching, but a crown is recommended in the adult. 55% of the teeth will rebound (discolor again).

Complications of Treatment: What are the common signs of a sodium hypochlorite accident?

According to Hulsmann & Hahn: 1. Immediate, severe pain. 2. Immediate edema. 3. Profuse intra-canal bleeding 4. Ecchymosis 5. Bad taste and irritation if the sinus is involved. 6. Secondary infection 7. Paresthesia

Complications of Treatment: How do you manage a sodium hypochlorite accident when it occurs?

According to Hulsmann & Hahn: 1. Pain control (local anesthesia and analgesics) 2. Initial cold compress (first 24 hours) 3. Warm compress after 24 hours 4. Antibiotics if there is a sign of infection 5. Emergency medical referral if vital signs are compromised.

Application of Biologic Principles: What is the effect of chlorhexidine on soft tissue inflammation?

According to Kim, using pre- and post-operative rinses reduces soft tissue inflammation.

Prognosis: what is the success rate for surgical endodontics?

According to Kim: 97% at 1 year 91% at 5 years According to Setzer (2010): 59% with traditional techniques 94% with modern techniques

Complications of Treatment: You complete a root end surgery, and your patient returns with a complaint of paresthesia. You don't suspect complete severance of a nerve. What is the timeline for healing?

According to Kim: Normal sensation should recur in approximately 4 weeks.

Anatomy: what nerve fibers found in the pulp are responsible for altering pulp blood flow?

According to Kim: C-fibers

Anatomy: What is dentin made of?

According to Kinney: 50% Mineral 30% Type I Collagen 20% Water

Treatment: Describe the Master Apical Impression Technique.

According to Knapp & Marshall (1972) Get a cone 2-3 sizes larger than your MAF, make sure it binds 1-2mm short of your working length. Dip the cone in chloroform, and gently insert the cone into the canal until it reaches your working length. Take a cone-fit radiograph. remove the cone after a few minutes, place sealer, and immediately replace. Backfill as usual.

Complications of Treatment: You have a non-healing periapical lesion, and opt to conduct root end surgery. Should you biopsy the contents of the lesion upon access?

According to Koivisto: Absolutely. Non-healing radiolucent jaw lesions other than granulomas or cysts were reported more than 20% of the time.

Application of Biologic Principles: what are the limits for anesthetic administration in healthy patients, patients with cardiovascular disease, and patients with severe cardiovascular disease?

According to Milam: epinephrine should be limited to 0.2mg for healthy patients (11 cartridges of 1:100K epi) -limited to 0.1mg for patients with a history of cardiovascular disease (5 cartridges) -limited to 0.04mg for patients with severe cardiovascular disease (2 cartridges)

Treatment: Can you use 2% Lidocaine 1:50,000 epi in a PDL injection? An IO injection?

According to Lin: 1:50K epi is safe to use in a PDL injection in a healthy patient. However, it is not safe to use for an IO injection. Don't do it!

Application of Biologic Principles: You're doing a root-end surgery. Should you prescribe an antibiotic since you're about to open the alveolus to the external environment?

According to Lindeboom (2005): There is no evidence that prophylactic antibiotics are effective prior to surgery.

Diagnosis: How can you be sure that the periapical radiolucency you observe on the radiograph is a granuloma?

According to Linenburg, the only sure way to tell if it is a granuloma or a cyst is to observe a sample of the tissue microscopically. Histologically: 62% Granulomas 28% Cysts 10% abscesses or periodontitis

Medical History: Your patient has asthma. What else do you want to know?

According to Little and Falace: 1. Get a good medical history 2. When was the onset? 3. What makes it worse/better? 4. Frequency/level of control 5. What medications are they on? 6. Do they have a rescue inhaler, did they bring it with them to the appointment? 7. Have they needed emergency care for it?

Medical History: Your patient is taking Propanolol, but they cannot remember why. What precautions must you take with this patient?

According to Little and Falace: Propanolol is a non-selective β-Blocker, used for controlling HTN. Monitor their vitals, and do not give more than 2 cartridges of 1:100K epi.

Application of Biologic Principles: How much epinephrine is contained in 1 cartridge of 2% Lidocaine 1:100K epi?

According to Little, 0.017mg

Application of Biologic Principles: What is the maximum dose of 2% Lidocaine that an adult patient can receive?

According to Little, 500mg

Application of Biologic Principles: Where are amino-amide anesthetics metabolized and excreted?

According to Milam: metabolized by liver microsomal enzymes and excreted by the kidneys. Esters (Novacaine): metabolized

Anatomy: Where is the the superior border of the mandibular canal typically located relative to the apices of the mandibular 1st and 2nd molars?

According to Littner (1986): 3.5-5.4mm inferior to the root apices of the mandibular molars. The canal was NEVER located in close proximity to the apices in both the vertical and B-L planes.

Anatomy: What is the relationship between the apices of the lower molars and the mandibular canal?

According to Littner, the superior border of the mandibular canal was located 3.5-5.4mm inferior to the root apices of both the 1st and 2nd molars. According to Denio and Torabinejad: The mandibular canal is typically an S-shaped pattern when viewed in a transverse plane. It starts on the buccal of #31, extends apical to the mesial root of 31; it then courses lingual to #30, and it finally curves either apical to #29 or buccal to it before exiting as the mental foramen. Incidences: S-Shaped: 31% Unable to determine: 28% Lingual: 19% Buccal: 17% Directly Inferior: 5% *For mandibular apical surgery, CBCT is a must.*

Radiographic Examination: Compare CBCT with 2D radiographs with regards to identifying periapical lesions

According to Low (2008), CBCT is found 34% more lesions than traditional radiographs.

Radiographic Examination: What is the relationship between the mucosal lining of the maxillary sinus, and apical periodontitis?

According to Lu et al (2012), the prevalence of mucosal thickening increased dramatically as the severity of apical periodontitis increased.

Application of Biologic Principles: What are four ways that you as a dentist can minimize bacterial resistance?

According to Montgomery (1984): 1. Only when there is a well-established need 2. Selecting the proper agent on the basis of Abx susceptibility tests 3. Using Abx systemically instead of topically 4. Initiating adequate dosage & duration to suppress the growth of 1st and 2nd step Abx resistant mutants.

Application of Biologic Principles: "Doc, I've been taking Ibuprofen, and it's just not working very well. Is there anything else I can take that will work?"

According to Menhinick: The combination of Ibu and APAP was superior to either drug alone in the alleviation of postoperative discomfort.

Prognosis: What is the success rate for a perforation repair with MTA?

According to Mente: 86% at one year

Application of Biologic Principles: What are the 3 primary indications for the use of antibiotics in dentistry?

According to Montgomery (1984): 1. Tx of acute dental infections 2. Prophylaxis for patients at risk of infective endocarditis. 3. Prophylaxis for patients with a compromised immune system.

Application of Biologic Principles: Will the use of bupivicaine assist in the reduction of post-operative pain?

According to Moore: yes. Patients on bupivicaine reported significantly less post-operative pain compared to placebo.

Treatment/Pathogeneis: Is AH+ sealer effective at killing E. Faecalis?

According to Mickel (2003), no. It has no known antimicrobial agent in it. According to Saleh (2004), yes. There were 0 CFUs found in their study after treating it AH+ and Grossman's sealer. Stuart (2006) verified the efficacy of AH+ and Grossman's sealer against E. Faecalis.

Application of Biologic Principles: why are vasoconstrictors added to local anesthetics?

According to Milam: 1. increase the duration of anesthetic effect. 2. alter the systemic uptake of the anesthetic, thus reducing potential systemic toxicity 3. provide hemostasis in the injected area.

Application of Biologic Principles: What are the two classifications of local anesthetics?

According to Milam: Amino-esters (novacaine) Amino-amides (lidocaine, etc)

Application of Biologic Principles: what anesthetics are the most effective in a low tissue pH environment (i.e. infection)?

According to Milam: Anesthetics with the lowest pKa values.

Diagnosis: What value do the EPT numbers have?

According to Mumford (1967), there is no value to the numbers. Either the tooth responds to EPT, or it does not.

Pathogenesis: What is the minimum remaining dentinal thickness required to avoid evidence of pulpal injury?

According to Murray: 0.5mm

Medical History: What is the only absolute contraindication for using vasoconstrictors in dentistry?

According to Milam: Patients diagnosed with Thyrotoxicosis (vasoconstrictors can cause "Thyroid Storm," which is a combination of HTN, delerium, vasomotor collapse.

Application of Biologic Principles: What are the two organ systems most profoundly affected by local anesthetics?

According to Milam: The Central Nervous System and the Cardiovascular System

Application of Biologic Principles: What part of local anesthetics produce toxic effects first, the anesthetic or the vasoconstricor?

According to Milam: The vasoconstrictor

Treatment: why do you store gutta percha in the refrigerator?

According to Oliet (1977): lowering the temperature of the gutta percha slows the rate of changes in its physical properties. *According to Sorin: gutta percha can be rejuvenated*

Objective Examination: Which pulp test provides an absolutely reliable indicator of the pulp's histological status?

According to Seltzer (1963): that test does not exist. Our pulp tests are subjective in nature, therefore they do not always corelate with the histological status of the pulp. Riccuci found an 84%-97% agreement with clinical and histological diagnoses using current testing methods.

Complications of Treatment: What compounds are formed when silver points corrode?

According to Seltzer (1972): Silver sulfides, silver sulfates, silver carbonates, silver amines, and sliver amide hydrates. These are cytotoxic.

Complications of Treatment: How do you manage a flare-up?

According to Seltzer (1985): 1. Relief of Occlusion 2. Premedicate the chamber or root canal at first appointment 3. Establishment of drainage 4. Intra-canal medicaments (don't force it beyond the apex) 5. Systemic drugs: corticosteroids are great, antibiotics aren't (Unless there are signs of cellutis/systemic infection) 6. Analgesics

Trauma: A patient presents to your office with an avulsed #9. What is the first step in the appropriate management of this patient?

According to Steelman, a rapid physical assessment needs to be done, including the following: A: Airway B: Breathing C: Circulation D: Disability (Neurological - did they lose consciousness?) E: Exposure (Radiographic exam)

Pathogenesis: The Acute Inflammatory Response is determined by: A. The cause of the injury B. The severity of the injury C. The location of the injury D. The angle of entry of the injury.

According to Trowbridge: B. The Severity of the injury. "The vascular response to injury is variable and may be reversible. The amount of variability and reversibility depends more upon the severity of injury than the kind of injury."

Pathogenesis: List some of the causes of chronic inflammation.

According to Trowbridge: Bacteria (living and dead), foreign bodies (eg, silica dust), chemical substances, products of metabolism (eg, urate crystals), and hypersensitivity reactions.

Pathogenesis: Why does chronic inflammation often go unnoticed?

According to Trowbridge: Because it usually does not produce the cardinal signs of inflammation such as pain, swelling, and redness.

Pathogenesis: In periapical lesions, why does the ratio of anaerobes to facultative bacteria increase with time?

According to Trowbridge: Because the availability of oxygen decreases as the pulp undergoes necrosis.

Pathogenesis: What is meant by the term "biphasic" response?

According to Trowbridge: Biphasic means that there is an immediate increase in vascular permeability followed first by a decrease and later by another increase.

Pathogenesis: How does IgE sensitize tissues?

According to Trowbridge: By attaching to mast cells and basophils through the Fc portion of the antibody molecule.

Pathogenesis: How is Hageman factor activated?

According to Trowbridge: By coming into contact with collagen or basement membrane in the walls of damaged blood vessels.

Pathogenesis: How do PMNs utilize molecular oxygen to destroy microorganisms?

According to Trowbridge: By converting oxygen to free radicals that are bactericidal.

Pathogenesis: Unfortunately, the antimicrobial agents within the PMN can't discriminate between microbes and host tissue. When these agents are activated, how can they contribute to disease?

According to Trowbridge: By damaging host tissue (free radicals, proteolytic enzymes).

Pathogenesis: How is the host protected against oxygen-derived free radicals?

According to Trowbridge: By enzymes such as superoxide dismutase and catalase; antioxidants like vitamin E and glutathione.

Pathogenesis: What is the most abundant complement component in the serum?

According to Trowbridge: C3

Pathogenesis: In complement activation, activation of either the classic pathway or the alternative pathway results in the formation of a key enzyme. What enzyme is it?

According to Trowbridge: C3 Convertase.

Pathogenesis: Which complement component is a chemotactic factor for neutrophils?

According to Trowbridge: C5a.

Pathogenesis: The HIV virus binds to which receptor on T cells?

According to Trowbridge: CD4

Pathogenesis: Name the neuropeptides that initiate neurogenic inflammation.

According to Trowbridge: CGRP (Calcitonin Gene-Related Peptide) and SP (Substance P)

Pathogenesis: What are histocompatibility antigens? What is their importance in organ transplantation?

According to Trowbridge: Cell surface antigens. They evoke rejection of transplanted tissue.

Pathogenesis: What is responsible for the acute type of graft rejection? Why does the chronic type of rejection progress so slowly? Under what conditions is the hyper-acute type of rejection likely to occur?

According to Trowbridge: Cell-mediated immunity, primarily involving cytotoxic T lymphocytes. Because the patient is usually receiving immunosuppressive therapy, which attenuates the immune response mediating the rejection. Preformed antigraft antibodies are in the patient's blood at the time of transplantation due to prior kidney transplant or blood transfusions.

Pathogenesis: What has to happen before emigration can occur?

According to Trowbridge: Cells must marginate.

Pathogenesis: In anaphylactic reactions, chemical mediators such as [BLANK] are released by [BLANK] and [BLANK], which are the principal target cells.

According to Trowbridge: Chemical mediators: -Histamine, -Prostaglandin D2, -Leukotrienes C4, D4, E4, -Eosinophil chemotactic factor of anaphylaxis Principle Target Cells: -Mast Cells -Basophils -platelet activating factor (PAF) are released by mast cells and basophils.

Pathogenesis: Which cells of the body serve as Class II antigen-presenting (accessory) cells and what do they do to initiate immune reactions?

According to Trowbridge: Class II antigen-presenting cells include dendritic cells, Langerhans' cells of the epidermis, macrophages, B cells, and endothelial cells. They present antigen to T- helper cells.

Pathogenesis: Which component(s) of complement mediate(s) vascular responses

According to Trowbridge: Cleavage of C2 results in formation of a kinin-like molecule. In addition, the anaphlatoxins C3a and C5a are vasoactive agents.

Pathogenesis: Why is the activation of C3 such a critical step in the complement cascade?

According to Trowbridge: Cleaveage of C3 yields C3a and C3b. C3b can bind to B, yielding C3b,B. C3b,B can stimulate further formation of C3a and C3b, and so on. *This is an important amplification mechanism.*

Pathogenesis: What two important components of fibrous connective tissue do fibroblasts secrete?

According to Trowbridge: Collagen and proteoglycans. Also, fibronectin

Pathogenesis: What tissue constituents do the metalloproteinases degrade?

According to Trowbridge: Collagen, fibronectin, proteoglycans, and laminin.

Pathogenesis: In immune complex reactions, the [BLANK] is activated. How are neutrophils involved in these reactions?

According to Trowbridge: Complement system. They respond chemically to complement components and release their lysosomal enzymes

Pathogenesis: What is involved in cicatrization?

According to Trowbridge: Contraction of a wound due to shortening of collagen fibers.

Pathogenesis: What produces gaps between endothelial cells?

According to Trowbridge: Contraction of endothelial cells

Pathogenesis: In delayed-type hypersensitivity, what do the effector cells release when they contact the antigen? Why is it a delayed response? Can you name a few clinical conditions that are associated with this response?

According to Trowbridge: Cytokines. It takes time for the lymphocytes that have been activated to undergo blast transformation, divide, and produce effector cells. Contact dermatitis, granulomatous disease, and autoimmune diseases.

Pathogenesis: Name two antigen-presenting cells in the pulp.

According to Trowbridge: Dendritic cell and macrophage.

Pathogenesis: How is the tensile strength of the skin restored following injury?

According to Trowbridge: Deposition of collagen and increased cross-linking of collagen molecules.

Pathogenesis: Chronic inflammation is a seesaw process involving cycles of [BLANK] and [BLANK]

According to Trowbridge: Destruction and repair.

Pathogenesis: In pyogenic osteomyelitis of the jaws, why does the bone become necrotic?

According to Trowbridge: Disruption of blood supply to the osteocytes by the formation of thrombi within blood vessels within the bone.

Pathogenesis: How does the system match the diversity of possible antigens?

According to Trowbridge: During differentiation of T cells or B cells, rearrangement of genes that code for the variable regions of antibody molecules provides for an almost limitless number of antigen-specific recognition units.

Pathogenesis: How does a keloid develop?

According to Trowbridge: Excessive formation of collagen.

Pathogenesis: What is "proud" flesh?

According to Trowbridge: Excessive proliferation of granulation tissue.

Pathogenesis: What is the difference between exudation and transudation?

According to Trowbridge: Exudation: an inflammatory process involving increased vascular permeability. Transudation: a non-inflammatory condition that results from one or more of the following: - increased intravascular hydrostatic pressure - decreased osmotic pressure in vessels - increased osmotic pressure in extravascular compartment.

Pathogenesis: What role does fibronectin play in healing?

According to Trowbridge: Fibronectin facilitates migration of inflammatory cells and epithelium into the wound, it is chemotactic for fibroblasts and macrophages, and it stimulates the release of fibroblast GF from macrophages.

Pathogenesis: Following bone fracture, the blood clot is replaced by a [BLANK], which bridges the fracture site.

According to Trowbridge: Fibrous callus.

Pathogenesis: What is the process of exudation?

According to Trowbridge: Fluid, plasma proteins, or cells leave the vessels and enter the tissues.

Pathogenesis: What is the role of plasmin in the vascular response to injury?

According to Trowbridge: Formation of kinins. Formation of vasoactive peptides from fibrin and fibrinogen.

Pathogenesis: Name a cytokine that is involved in macrophage activation.

According to Trowbridge: Gamma interferon. (Also, granulocyte-macrophage colony-stimulating factor.)

Pathogenesis: What is hemoconcentration, and why is it important for inflammation?

According to Trowbridge: Hemoconcentration is an increased viscosity in blood due to the leakage of inflammatory mediators at the site of injury. As the inflammatory mediators cross the endothelium, the red blood cells are left behind, thus increasing the viscosity. This increased viscosity causes a traffic jam at the site of injury, which is good because the incoming inflammatory mediators will be held up long enough for them to cross the leaky endothelium and into the injury site.

Pathogenesis: Which cells produce acute phase proteins?

According to Trowbridge: Hepatocytes.

Pathogenesis: In cellulitis, what bacterial products cause spreading and diffuse inflammation?

According to Trowbridge: Hyaluronidase and fibrinolysin.

Pathogenesis: When activated, what can the lysosomal enzymes do?

According to Trowbridge: Hydrolyze various types of molecules found in cells and tissues.

Pathogenesis: How does one recognize hyperalgesia in a tooth?

According to Trowbridge: Hyperalgesia causes a tooth to become sensitive to hot and cold foods and beverages.

Pathogenesis: Which interleukin causes the release of neutrophils from the bone marrow?

According to Trowbridge: IL-1

Pathogenesis: Fever is evoked by which cytokines?

According to Trowbridge: IL-1/TNF

Pathogenesis: The activity of eosinophils is often related to elevated levels of a specific immunoglobulin. Which one?

According to Trowbridge: IgE.

Pathogenesis: Which immunoglobulin is the primary mediator of immediate hypersensitivity?

According to Trowbridge: IgE.

Pathogenesis: Which is the first immunoglobulin to be synthesized in a primary immunologic response?

According to Trowbridge: IgM

Pathogenesis: Which immunoglobulin is associated With a primary immune response? With a secondary immune response?

According to Trowbridge: IgM IgG.

Pathogenesis: Name the two types of granulomas.

According to Trowbridge: Immune and foreign body.

Pathogenesis: Which reaction(s) involve(s) complement-fixing antibodies?

According to Trowbridge: Immune cytotoxic and immune complex reactions.

Pathogenesis: How does granulation tissue differ from chronic inflammatory tissue?

According to Trowbridge: In general, granulation tissue contains fewer inflammatory elements.

Pathogenesis: How does the immune cytotoxic reaction differ from the immune complex reaction? What result does the activation of complement have in this reaction?

According to Trowbridge: In the immune cytotoxic reaction the antigen involved is situated on the membrane of cells, whereas immune complexes represent the union of soluble antigens and antibodies. Chemotactic attraction of PMNs and the formation of anaphylatoxins

Pathogenesis: Where do T-cells mature?

According to Trowbridge: In the thymus gland.

Pathogenesis: What causes heat and redness in an acute inflammatory response?

According to Trowbridge: Increase in blood flow in the injured part.

Pathogenesis: What is meant by "active hyperemia"?

According to Trowbridge: Increased blood flow in arterioles, capillaries, and venules.

Pathogenesis: How does vascular stasis develop?

According to Trowbridge: Increased vascular permeability leading to loss of fluid from vessels and hemoconcentration. Leukocyte margination contributes by increasing resistance to blood flow.

Pathogenesis: Macrophage activation is of great importance in certain disease processes. Why? How can macrophage activation injure host tissue?

According to Trowbridge: -Activated macrophages have a greater ability to kill and digest microorganisms and malignant tumor cells than non-activated macrophages. This is particularly true in granulomatous diseases such as tuberculosis and leprosy. -Formation of free radicals and release of proteolytic enzymes such as collagenase and elastase.

Pathogenesis: Examples of anaphylactic reactions are:

According to Trowbridge: -Anaphylactic shock, -asthma, -drug allergy, -hay fever, and -chronic rhinitis.

Pathogenesis: What does relaxation of the precapillary sphincters accomplish?

According to Trowbridge: Increases blood flow in capillary bed by allowing more blood to enter capillaries and opening inactive capillaries.

Pathogenesis: How do phagocytes adhere to endothelial surfaces?

According to Trowbridge: Interaction between specific adhesion molecules present on the surfaces of leukocytes and endothelial cells.

Pathogenesis: Which interleukin drives cell-mediated immunity?

According to Trowbridge: Interleukin-12, by promoting the generation of Th1 CD4+ cell (cytokine production) and CTL responses (cell-mediated cytotoxicity).

Pathogenesis: What happens when a lymphocyte is presented (i.e. "recognizes") the antigen to which it is pre-committed?

According to Trowbridge: It becomes activated.

Pathogenesis: besides lymphatics, how else can fluid be removed from an injury site?

According to Trowbridge: It can be drained by blood vessels, particularly the venules.

Pathogenesis: During vasodilation and increased vascular permeability, how can excess fluid be removed from the pulp?

According to Trowbridge: It can be resorbed by blood vessels and lymphatics.

Pathogenesis: How does nitric oxide promote vasodilation?

According to Trowbridge: It induces vascular smooth muscle relaxation.

Pathogenesis: Characterize the initial inflammatory reaction that develops in response to caries.

According to Trowbridge: It is basically a cell-mediated immune response to bacterial products (antigens) diffusing from the carious lesion into the pulp.

Pathogenesis: Why is the pulp similar to the brain, bone marrow, and nail beds in its environment?

According to Trowbridge: It is in a low-compliance environment and therefore is unable to swell during acute inflammation like most other tissues.

Pathogenesis: How can a chronic abscess be recognized histologically?

According to Trowbridge: It is surrounded by chronic inflammatory tissue.

Pathogenesis: What is the special role of IgA?

According to Trowbridge: It is the primary host defense mechanism at the epithelial surfaces of various membranes (eg, gut, respiratory system, mucous membranes) and glands (eg, salivary, lacrimal)

Pathogenesis: How does neurogenic inflammation develop?

According to Trowbridge: Antidromic sensory impulses cause the release of neuropeptides from unmyelinated nerve fibers. These mediators produce vasodilation and increased vascular permeability.

Pathogenesis: Hypersensitivity Types I, II, and Ill involve the union of [BLANK] and [BLANK]

According to Trowbridge: Antigen and antibody.

Pathogenesis: What protection do tissues have against the actions of proteolytic enzymes?

According to Trowbridge: Antiproteinases.

Pathogenesis: From what precursor molecule are the prostaglandins and leukotrienes derived?

According to Trowbridge: Arachidonic Acid

Pathogenesis: What is an antigenic determinant?

According to Trowbridge: Areas of the surface of antigen molecules that determine the antigenicity of the molecule.

Pathogenesis: How are neuropeptides SP and CGRP released from sensory nerve terminals?

According to Trowbridge: Axon reflex (antidromic stimulation)

Pathogenesis: What is the chief difference between B and T lymphocytes and NK cells?

According to Trowbridge: B and T cells recognize antigen whereas NK cells do not. Consequently NK cells can be mobilized quickly.

Pathogenesis: What cell is the progenitor of plasma cells? What is meant by polyclonal B-cell activation?

According to Trowbridge: B cell.

Pathogenesis: In immunology, what is meant by the term "pre-committed"?

According to Trowbridge: It means that an immunologically competent cell is specifically programmed to recognize a particular anti- gen before it actually encounters it for the first time.

Pathogenesis: How does interleukin-1 affect activated lymphocytes?

According to Trowbridge: It supports the proliferation of B cells and T cells.

Pathogenesis: What is the role of kallikrein in inflammation?

According to Trowbridge: Kallikrein cleaves kininogen to produce bradykinin. It can also activate Hageman factor.

Pathogenesis: AIDS patients are at risk for certain malignant neoplasms. Can you name them?

According to Trowbridge: Kaposi's sarcoma, lymphomas.

Pathogenesis: Products of PMN respiration have antimicrobial properties. Which metabolites are involved?

According to Trowbridge: Lactic acid, hydrogen peroxide, hydroxyl radical, and hypochlorous acid.

Pathogenesis: What is leukocyte margination and what is its role in inflammation?

According to Trowbridge: Leukocyte margination, aka pavementing, is the process whereby leukocytes (white blood cells) begin to stick to the post-capillary venules, which further retard the flow of blood.

Pathogenesis: What are the components of SRS-A and what types of responses do they mediate?

According to Trowbridge: Leukotrienes C₄, D₄, and E₄. SRS-A produces bronchospasm, vasodilation, increased vascular permeability, and it stimulates mucus secretion.

Pathogenesis: Which substance(s) mediate(s) the so-called immediate transient phase of vascular permeability?

According to Trowbridge: Histamine

Pathogenesis: What is the duration of action of histamine?

According to Trowbridge: Histamine's action is of short duration - probably only a few minutes.

Pathogenesis: What substances do basophil granules contain?

According to Trowbridge: Histamine, heparin.

Pathogenesis: Name a chemical mediator in inflammation that is preformed and stored in cells.

According to Trowbridge: Histamine.

Pathogenesis: Why is there a close relationship between chronic inflammation and repair?

According to Trowbridge: Like granulation tissue, chronic inflammatory tissue contains fibroblasts, collagen, macrophages, and vascular elements.

Pathogenesis: What do the granules of basophils contain?

According to Trowbridge: Like mast cells they contain histamine and heparin.

Pathogenesis: Name some of the important local factors influencing repair. Name the systemic factors.

According to Trowbridge: Local: infection, hemorrhage, crushing of tissue, foreign objects, excessive mobility, and presence of vascular Systemic: nutrition, presence of disease, certain hormones, and condition of the circulation.

Etiology: What is the etiology of focal sclerosing osteomyelitis? Radiographic Exam: Why is it a radiopaque lesion?

According to Trowbridge: Long-standing, low-grade infection of the dental pulp. Proliferation of osseous tissue.

Pathogenesis: What causes hemoconcentration?

According to Trowbridge: Loss of fluid from the bloodstream resulting in an increase in the concentration of red blood cells.

Pathogenesis: What are the effects of corticosteroids on the immune system?

According to Trowbridge: Low concentrations of corticosteroids stimulate some immunologic responses, higher concentrations are inhibitory.

Pathogenesis: Characteristically, what inflammatory cells are present in a chronic lesion?

According to Trowbridge: Lymphocytes, macrophages, plasma cells (not always), usually some neutrophils and eosinophils.

Pathogenesis: Which leukocytes are found in periapical granulomas? Which of them is thought to be the most important in orchestrating the immune response?

According to Trowbridge: Lymphocytes, plasma cells, macrophages, neutrophils, and eosinophils. T-helper cells.

Pathogenesis: What types of substances are contained within PMN granules?

According to Trowbridge: Lysosomal enzymes, cytolytic proteinases, cationic proteins, lysozyme, lactoferrin, and myeloperoxidase.

Pathogenesis: What factors in a chronic inflammatory response can lead to tissue injury?

According to Trowbridge: Lysosomal enzymes, cytotoxic T lymphocytes, cytokines, and immune complexes.

Pathogenesis: What are lysosomes? What is their physiologic role? Which cells have them?

According to Trowbridge: Lysosomes: Intracellular organelles containing acid hydrolases (lysosomal enzymes). Role: Digestion of intracellular matter or materials brought into the cell by phagocytosis. All cells have them.

Pathogenesis: What are some basic differences between neutrophils and macrophages?

According to Trowbridge: Macrophages are larger, live longer, usually arrive at site of injury after neutrophils, are better able to phagocytize particulate matter, and secrete a large number of biologically active substances.

Pathogenesis: In AIDS, which cells serve as reservoirs for the dissemination of the virus?

According to Trowbridge: Macrophages.

Pathogenesis: Which of the leukocytes plays a lead role in foreign body reactions?

According to Trowbridge: Macrophages. These may fuse to form foreign body giant cells.

Pathogenesis: How is fever beneficial to the host?

According to Trowbridge: Many bacteria are sensitive to even small increases in body temperature.

Pathogenesis: An important role of PMNs is to phagocytize microorganisms. What happens to this material after it is brought into the cell?

According to Trowbridge: Microbes are killed by antibacterial agents (if possible), and the remains are digested by lysosomal enzymes.

Pathogenesis: In epithelialization, migration is one of three cellular responses to wounding. What are the other two?

According to Trowbridge: Multiplication and maturation.

Pathogenesis: Which cells are primarily responsible for the contraction of wounds?

According to Trowbridge: Myofibroblasts.

Pathogenesis: Where are the antigen-binding sites on immunoglobulin molecules?

According to Trowbridge: N-terminals of the F(ab) pieces of the molecule.

Pathogenesis: Which enzyme is involved in the initiation of free radical formation?

According to Trowbridge: NADPH oxidase.

Pathogenesis: Name some defense reactions involving antibodies

According to Trowbridge: Neutralization, agglutination, precipitation, cell lysis, opsonization, and complement activation.

Pathogenesis: Which leukocytes are the first to migrate to an area of injury?

According to Trowbridge: Neutrophils.

Pathogenesis: What is organization with respect to wound healing?

According to Trowbridge: Organization involves the conversion of a blood clot, an exudate, or necrotic tissue into fibrous connective tissue

Pathogenesis: What cells are responsible for internal resorption of dentin?

According to Trowbridge: Osteoclasts.

Pathogenesis: In chronic inflammation, how does scarring occur?

According to Trowbridge: Parenchymal cells are destroyed and replaced by fibrous connective tissue.

Pathogenesis: What is responsible for the maintenance of chronicity?

According to Trowbridge: Persistence of the causative agent, resulting in sustained presence of inflammatory cells.

Pathogenesis: What is our first line of defense against infections?

According to Trowbridge: Phagocytes (both neutrophils and macrophages)

Pathogenesis: Once inside the phagocyte, in what structure is bacteria encapsulated?

According to Trowbridge: Phagocytic vacuole.

Pathogenesis: Eosinophils, like PMNs, respond to chemotactic stimuli. Name two important chemotactic factors.

According to Trowbridge: Platelet activating factor, leukotriene B₄.

Pathogenesis: From which vessels does emigration of blood leukocytes occur?

According to Trowbridge: Post-capillary venules.

Pathogenesis: Which type(s) of vessels become(s) more permeable in mild injury?

According to Trowbridge: Post-capillary venules.

Pathogenesis: What important function of IgA prevents colonization of bacteria?

According to Trowbridge: Prevents bacteria from adhering to surfaces by binding to attachment sites on the bacterial cell wall.

Pathogenesis: How do macrophages become activated?

According to Trowbridge: Primarily by T lymphocyte macrophage-activating cytokines such as γ interferon and granulocyte- macrophage colony-stimulating factor.

Pathogenesis: What determines the type of inflammatory response that develops in response to an infected root canal?

According to Trowbridge: Primarily the virulence of the bacteria.

Pathogenesis: Whereas acute inflammation involves exudative reactions, chronic inflammation is associated with [BLANK] responses.

According to Trowbridge: Proliferative.

Pathogenesis: The majority of antigens are what kind of molecule?

According to Trowbridge: Protein molecules.

Pathogenesis: What cells give rise to replacement odontoblasts?

According to Trowbridge: Pulp fibroblasts.

Pathogenesis: A periapical abscess is associated with what kind of exudate?

According to Trowbridge: Purulent.

Pathogenesis: During chemotaxis, what occurs within phagocytes that enables them to move in a certain direction?

According to Trowbridge: Rearrangement of cytoskeletal microtubules and microfilaments.

Pathogenesis: How does the secondary immune response differ from the primary immune response?

According to Trowbridge: Recognition of antigen by memory cells. This results in the production of specific antibody in less time than in the primary response.

Pathogenesis: The three requirements of the immune system are:

According to Trowbridge: Recognize. React. Remember.

Pathogenesis: How does a serous exudate differ from a fibrinous exudate?

According to Trowbridge: Serous exudate is fluid that is low in protein, whereas a fibrinous exudate is rich in protein, particularly fibrinogen.

Pathogenesis: In the rejection of a foreign tissue graft, what antigens are involved? Which genes code for these antigens? Where are the antigens located?

According to Trowbridge: Histocompatibility (HLA) antigens. Major histocompatibility complex (MHC). On the surface of cells.

Pathogenesis: Healing is a component of the inflammatory process. In what ways is it similar to inflammation? To chronic inflammation?

According to Trowbridge: Similarities to acute inflammation: increased vascular permeability, emigration of leukocytes, phagocytosis. Similarities to chronic inflammation: emigration of leukocytes, vascular proliferation, fibrogenesis.

Pathogenesis: What risk factors are associated with periodontal disease?

According to Trowbridge: Smoking, increasing age, poor oral hygiene, diabetes mellitus, and AIDS.

Pathogenesis: What are cytokines?

According to Trowbridge: Soluble products of cells of the immune system. They can modify the behavior of other cells and produce systemic effects.

Pathogenesis: What is Starling's law and how does it relate to vascular reactions?

According to Trowbridge: Starling's Law deals with the relationship between hydrostatic pressure and osmotic pressure in the movement of fluid in and out of arterioles, capillaries, and venules.

Pathogenesis: Why do leukocytes accumulate at a site of injury? Why do leukocytes stop accumulating at an injury site?

According to Trowbridge: Start: Because of chemotactic influences. Stop: Agents responsible for initiating chemotactic activity are inactivated or destroyed.

Radiographic Exam: How can a periapical granuloma be distinguished from a cyst, radiographically?

According to Trowbridge: Studies have shown that it is not possible to differentiate a cyst from a granuloma.

Pathogenesis: What are opsonins?

According to Trowbridge: Substances that enhance phagocytosis by helping leukocytes to adhere to cells to be ingested.

Pathogenesis: Which cells have the best regenerative capacity? Which cells retain the latent capacity to divide? Which cells have lost the ability to regenerate?

According to Trowbridge: Surface epithelial cells, blood-forming cells, and lymphoid cells. Parenchymal and mesenchymal cells. Neurons and striated muscle cells.

Pathogenesis: What is meant by polyclonal B-cell activation?

According to Trowbridge: T cell-independent activation by antigens are typically polymeric and large in size with repeating antigenic sequences.

Pathogenesis: Where in the lymph nodes and spleen are T-cells located? Where are the B-cells?

According to Trowbridge: T cells are located mainly in the paracortical area, B cells in the germinal centers.

Pathogenesis: What does the graft-versus-host reaction involve?

According to Trowbridge: T cells in the donor organ respond to HLA on the cells of the host. Cytotoxic T lymphocytes and lymphokine-producing lymphocytes mediate an attack on these cells, causing tissue injury.

Pathogenesis: Which cells of the immune system orchestrate chronic inflammatory reactions?

According to Trowbridge: T-helper cells and macrophages

Pathogenesis: Which cytokine is associated with cachexia?

According to Trowbridge: TNF-α (also called cachectin).

Pathogenesis: What is the metabolic pathway by which the leukotrienes are formed?

According to Trowbridge: The Lipoxygenase Pathway

Pathogenesis: What is the primary goal of the immune system?

According to Trowbridge: The elimination of antigen.

Pathogenesis: What is the origin of the epithelium that lines periapical cysts?

According to Trowbridge: The epithelial rests of Malassez.

Pathogenesis: What is the main difference between healing by primary intention healing by secondary intention?

According to Trowbridge: The extent of injury (ie, the amount of tissue that must replaced by fibrous connective tissue).

Pathogenesis: What happens when a neutrophil degranulates?

According to Trowbridge: The granules fuse with the phagocytic vacuole and release their contents into the vacuole.

Pathogenesis: What is the predominant inflammatory cell in a periapical abscess?

According to Trowbridge: The neutrophil.

Pathogenesis: What are the biologic functions of the Fc piece of the immunoglobulin molecule?

According to Trowbridge: The pharmacologic properties of the molecule, for example, complement fixation, binding to Fc receptors on inflammatory cells (opsonization, cytotoxicity, etc), and mast cells.

Pathogenesis: What is "active hyperemia"?

According to Trowbridge: The process of increased blood delivery to an injury site, whereby the local arterioles vasodilate and the site becomes congested with blood. The resultant increase in capillary activity can lead to as much as 10x the amount of blood in the area.

Pathogenesis: What determines the duration of the vascular response to injury?

According to Trowbridge: The severity of the injury determines the extent to which the chemical mediators that control the vascular response are produced or released.

Pathogenesis: What is the most important factor in determining the extent of the immediate acute response?

According to Trowbridge: The severity of the injury.

Pathogenesis: What is the histologic pattern of the chronic inflammatory response?

According to Trowbridge: The tissue is infiltrated by chronic inflammatory cells (lymphocytes, macrophages), and fibroblasts and collagen are present.

Pathogenesis: What happens during the respiratory burst in PMNs?

According to Trowbridge: There is a sharp increase in oxygen consumption with formation of reduced forms of oxygen (oxygen-derived free radicals).

Pathogenesis: When does acute inflammation stop and chronic inflammation begin?

According to Trowbridge: There is no clear dividing line and much overlap.

Pathogenesis: What is the importance of recognition units? Where are they located? Of what do they consist?

According to Trowbridge: They allow the T cell or B cell to recognize an antigen. On the cell surface. They are antibody molecules that can bind to antigenic determinants

Pathogenesis: What is an important property of pyogenic bacteria?

According to Trowbridge: They are resistant to phagocytosis.

Pathogenesis: What is the major role of eosinophils in host defense?

According to Trowbridge: They are the first line of defense against parasites.

Pathogenesis: How do growth factors work?

According to Trowbridge: They cause cells to migrate, proliferate, differentiate, and secrete proteins. Remember, different growth factors have different effects on cells.

Pathogenesis: How do regulatory cytokines affect cells?

According to Trowbridge: They cause them to proliferate and differentiate.

Pathogenesis: What happens to mast cells when antigen combines with lgE molecules attached to their surface membranes?

According to Trowbridge: They degranulate, releasing histamine and other inflammatory agents.

Pathogenesis: What must happen before cytotoxic T cells can kill a target cell?

According to Trowbridge: They must come into direct contact with the target cell.

Pathogenesis: In inflammation, what do lymphatics do besides remove fluid from the tissues?

According to Trowbridge: They perform an important function by removing leukocytes, cellular debris, plasma proteins, and fibrin.

Pathogenesis: What is Starling's Law?

According to Trowbridge: This is the law whereby fluid moves across the endothelial layer of capillaries. The movement is dictated by intravascular hydrostatic pressure, and extravascular osmotic pressure.

Pathogenesis: Why is wound debridement necessary? Which leukocytes are primarily responsible for debridement?

According to Trowbridge: To clear a path that fibroblasts and endothelial cells wound. Macrophages.

Pathogenesis: Name some granulomatous diseases.

According to Trowbridge: Tuberculosis, leprosy, sarcoidosis, brucellosis, and syphilis.

Pathogenesis: In an acute inflammatory response, which leukocytes emigrate from the vessels?

According to Trowbridge: Usually neutrophils.

Pathogenesis: What causes an acute periapical abscess to become a chronic abscess?

According to Trowbridge: Usually when drainage is established.

Pathogenesis: What is Vascular Stasis, and what is its role in the inflammatory process?

According to Trowbridge: Vascular stasis is when the venules at the injury site are completely occluded, thus shunting all inflammatory mediators to the site of injury. In mild injuries, this process can take 15-20 minutes. In severe injuries, vascular stasis can happen in a matter of minutes.

Pathogenesis: In acute inflammation, what causes tissues to swell?

According to Trowbridge: Vasodilation and increased vascular permeability. These result in increased intravascular hydrostatic pressure, reduced intravascular osmotic pressure, and increased osmotic pressure in the extravascular space.

Pathogenesis: What is the mechanism of action of bradykinin in inflammation?

According to Trowbridge: Vasodilation: increases vascular permeability.

Pathogenesis: What role does Hageman factor play in the activation of kinins?

According to Trowbridge: When activated, it gives rise to prekallikrein activator (PKA).

Pathogenesis: What is the role of antibody in complement activation?

According to Trowbridge: When it binds specifically to antigen, the structure of the antibody molecule is altered. This provides a binding site for C1q.

Pathogenesis: In caries, when does an abscess develop in the pulp?

According to Trowbridge: When proliferating bacteria enter or are quite near to the pulp.

Pathogenesis: Can chronic inflammation develop without an antecedent acute inflammatory response?

According to Trowbridge: Yes.

Pathogenesis: What are the signs/symptoms of vasodilation to an area of injury?

According to Trowbridge: vasodilation to an injured sight results in redness, heat, and swelling Increased blood flow = redness and heat Alterations in vascular permeability = increased fluid at the injury site = swelling

Complications of Treatment: What is the incidence of post-op flare ups?

According to Tsesis: 8.4%

Complications of Treatment/Medical History: a patient has a documented adverse reaction/allergy to local anesthetics. They need a dental procedure that require anesthetic. What is an acceptable alternative?

According to Uckan, Diphenhydramine (Benadryl) can be used as an acceptable alternative. Reader et al (The Ohio State Group) indicated that this injection is significantly more painful, and therefore must be used judiciously.

Treatment: How does maintaining apical patency affect the efficiency of your irrigation solution?

According to Vera (2012): maintaining patency decreased vapor lock in large canals, thus increasing irrigant efficiency at the canal apex.

Anatomy: where is lateral anatomy most commonly located?

According to Vertucci: in the apical third of the root.

Diagnosis: Describe the relationship between endodontic and periodontal lesions, according to Simon

Primary Endo, Secondary Perio is the most common Primary Perio, Secondary Endo is not common, thought that perio must extend to the apex for it to affect the pulp True Combined Lesion is very rare, lesions originate both endo and perio, and they combine.

Complications of Treatment: What is the risk of using Ibuprofen or ASA in a pregnant woman in her third trimester?

Prolonged pregnancy and delayed labor.

Radiographic Examination: What is Clark's rule?

Also known at the buccal object rule, or the SLOB Technique. Same Lingual, Opposite Buccal. Objects that are closer to the sensor (further from the cone) will move in the same direction as the placement of the tube head. Example: if the tube head is positioned mesially to #14 (and therefore angled distally), the palatal canal will appear mesially shifted on the radiograph when compared with the same tooth radiographed perpendicularly.

Radiographic Interpretation: What is the low-energy filter of a tubehead made out of?

Aluminum

Etiology: Is the infection of a root canal monobacterial or multibacterial?

Always multi-bacterial. Sundqvist demonstrated that a single strain of bacteria causes little to mild inflammation, but that when combined with other bacteria, they have the capability to for abscesses and transmissible infections.

Treatment: you are inserting your System B tip into a canal and activating it. Are you concerned about overheating the dental apparatus?

Always. According to Eriksson (1983): Any procedure that will cause a 10°+C rise in temperature will result in permanent damage to the surrounding bone. So...apply fast heat...

Etiology: Define saccharolytic.

Saccharolytic bacteria are ones that are capable of hydrolyzing (metabolizing) sugar molecules to produce energy. These are the Prevotella class of bacteria. The asaccharolytic bacteria are the Porphyromonas class

Pathogenesis: What is the difference between cellular immune response and humoral immune response?

Cellular immune response involves different cells reacting to an insult to tissue. Humoral immune response involves extra-cellular particles that facilitate the overall immune response. Cellular immune components: - Leukocytes - Macrophages - Lymphocytes Humoral immune components: - Immunoglobulins - Prostaglandins - Cytokines

Radiographic Interpretation: What does CCD stand for?

Charged-coupled device. It is composed of an electronic circuit embedded in several thin layers of silicon.

Prognosis: What is the 3-year post-operative success rates for Heithersay Class I-IV lesions?

Class I-II: 100% Class III: 78% Class IV: 12.5%

Application of Biologic Principles: Of the 7 common antibiotics used for endodontic infections, which antibiotics are bacteriostatic?

Clindamycin and Azithromycin. All others are bacteriocidal.

Treatment: Who first described the Serial Step-back Technique?

Coffae & Brilliant (1975).

Pathogenesis: Define "CFU."

Colony-Forming Unit.

Diagnosis: List the 5 categories for tooth fracture according to the AAE

Craze lines: affect only the enamel, often non-pathogenic; no treatment needed Fractured Cusp: Involves enamel and dentin; cuspal coverage with/without RCT Cracked Tooth: incomplete fracture, may extend into the pulp/radicular space; Cuspal Coverage with/without RCT or EXT Split Tooth: mesio-distal complete fracture, non-restorable, extending into canal space Vertical Root Fracture: stems from the root and extends coronally, usually presents with previously treated teeth, non-restorable.

Treatment: What is the difference between Cyclic and Torsional fatigue?

Cyclic Fatigue: breaking by excessive bending back and forth (larger instruments tend to break due to cyclic fatigue) Torsional Fatigue: breaking due to binding of the instrument at the tip (smaller instruments are more susceptible) Pruett (1997) NiTi rotary files tend to break more from torsional fatigue than from cyclic (Sattapan - 2000)

Prognosis: What conclusion regarding the 2-year outcome of endodontic retreatment did Gorni and Gagliani (2004) come to?

The outcome was directly related to the inability to non-surgically debride the infected canal space during retreatment of teeth with iatrogenically altered canal morphology.

Application of Biologic Principles: what factor affects the rate of onset of action of a local anesthetic?

The pKa value. The lower the pKa, the faster the onset of action.

Treatment: Describe the Rectangular/Trapezoidal Flap.

Advantages: 1. Excellent access and visualization. 2. No tension or tearing. 3. Good reference points for suturing. 4. More room for curettage & osseous resection. 5. Can do perio curettage & alveoplasty. 6. Maintains good blood supply. 7. Incision not over bony defect. Disadvantages: 1. Retraction is more difficult. 2. Gingival attachment disturbed. 3. Suturing may be more difficult.

Treatment: Describe the Triangular Flap.

Advantages: 1. Excellent access and visualization. 2. No tension or tearing. 3. Good reference points for suturing. 4. More room for curettage & osseous resection. 5. Can do perio curettage & alveoplasty. 6. Maintains good blood supply. 7. Incision not over bony defect. Disadvantages: 1. Retraction is more difficult. 2. Gingival attachment disturbed. 3. Suturing may be more difficult.

Radiographic Interpretation: Why must the cathode and anode be placed in a vacuum when generating high-velocity electron movement?

Air molecules are of greater density than electrons. Therefore, if those various air molecules (nitrogen, oxygen, methane, etc) are present, it will scatter the electrons, thus decreasing their ability to form directed, high-energy photons.

Treatment: What is the difference between Austenite Phase, R Phase, and Martensite phase?

These describe the different crystalline structures that NiTi instruments take when exposed to different temperatures (like the internal temperature of a tooth vs. the operatory temperature. According to Shen (2013): Austenite = Stiff R-Phase = Intermediate Martensite = Flexible

Complications of Treatment: according to O'Keefe, what is the relationship between operative/post-op pain and immediate pre-operative pain severity?

They are proportional. According to Harrison & Baumgartner, patients beginning RCT without symptoms are unlikely to experience inter-appointment pain that requires palliative treatment.

Pathogenesis: Ameloblastomas: Where are they typically located, and what symptoms do they have?

They are typically located in the posterior mandible and are generally asymptomatic. ...they're also aggressive little buggers that don't always read the text book, so don't be quick to count it out...

Application of Biologic Principles: What is the mechanism of action for the bacteriostatic antibiotics used to treat endodontic infections?

They both inhibit protein synthesis by binding to a portion of the bacterial ribosome. Note: with the exception of Metronidazole, all other antibiotics commonly used for endodontic infections are both bacteriocidal and inhibits the synthesis of the bacterial cell wall.

Radiographic Examination: Discuss "Radiographic Magnification Error" according to Burger et al (1999)

They found that regardless of technique used with digital radiography, 2D images resulted in canal lengths that were significantly different from the true length of the canal that was radiographed. Take home message: rely on your radiographic measurement for an estimate of canal length, and not a determination of it.

Treatment: What did Cambruzzi recommend using to assist in the surgical detection of isthmuses?

methylene blue dye.

Etiology: Pressure resorption occurs secondary to what?

1. misaligned tooth eruption 2. slow-growing tumors or cysts 3. orthodontic movements

Treatment: According to Stuart (2006), What are the 4 treatment recommendations for eradicating E. Faecalis from the root canal?

1. prepare the apical canal to larger file sizes. 2. Full-strength NaOCl with frequent replenishment. 3. EDTA to open dentinal tubules, therefore allowing your irrigant to reach the bacteria. 4. 2% CHX liquid used for a 2-minute rinse, or CHX gel as an inter-appointment medicament (placed for at least 7 days).

Treatment: What are the ADA/AHA accepted reasons for using antibiotic prophylaxis for the risk of infective endodcarditis?

1. prosthetic cardiac valves, including transcatheter-implanted prostheses and homografts; 2. prosthetic material used for cardiac valve repair, such as annuloplasty rings and chords; 3. a history of infective endocarditis; 4. a cardiac transplant with valve regurgitation due to a structurally abnormal valve; 5. the following congenital (present from birth) heart diseases: - unrepaired cyanotic congenital heart disease, including palliative shunts and conduits - any repaired congenital heart defect with residual shunts or valvular regurgitation at the site of or adjacent to the site of a prosthetic patch or a prosthetic device

Objective Examination: According to Guthrie, what are the top 10 typical signs of a cracked tooth?

1. sudden sharp pain when chewing 2. sensitivity to thermal changes, especially cold. 3. continual symptoms from weeks to months 4. patient's inability to localize the offending tooth 5. pain on lateral cuspal pressure 6. no pain on vertical percussion 7. a vital response to pulp testing 8. negative radiographic findings 9. weakened coronal tooth structure 10. bruxism or unusual chewing habits

Radiographic Interpretation: What does "tomography" mean?

"Sliced Imaging"

Application of Biologic Principles: You just took your last Metronidazole pill. How long do you need to wait before consuming alcohol? Do you ever prescribe Metronidazole to patients on lithium?

#1. You shouldn't be drinking anyway. It's a very bad habit. Wait at least three days. Don't prescribe it to patients on lithium. It will elevate blood levels of lithium, creating toxicity.

Root Canal Anatomy: Maxillary Canine

% w/ 1 Canal at the apex: 100 % w/ 2 Canals at the apex: 0 % w/ 3 Canals at the apex: 0 Pineda & Kuttler

Root Canal Anatomy: Maxillary Central Incisor

% w/ 1 Canal at the apex: 100 % w/ 2 Canals at the apex: 0 % w/ 3 Canals at the apex: 0 Pineda & Kuttler

Root Canal Anatomy: Maxillary Lateral Incisor

% w/ 1 Canal at the apex: 100 % w/ 2 Canals at the apex: 0 % w/ 3 Canals at the apex: 0 Pineda & Kuttler

Medical History: when do you prescribe an antibiotic prophylaxis for infective endocarditis?

(The short answer): 1. full/partial prosthetic heart valve 2. History of IE 3. Heart transplant w/ regurgitation due to an abnormal valve. 4. Congenital heart diseases (The long answer): From the ADA website (10 Aug 2018) The current infective endocarditis/valvular heart disease guidelines state that use of preventive antibiotics before certain dental procedures is reasonable for patients with: -prosthetic cardiac valves, including transcatheter-implanted prostheses and homografts; -prosthetic material used for cardiac valve repair, such as annuloplasty rings and chords; -a history of infective endocarditis; -a cardiac transplantation with valve regurgitation due to a structurally abnormal valve; The following congenital (present from birth) heart diseases: -unrepaired cyanotic congenital heart disease, including palliative shunts and conduits -any repaired congenital heart defect with residual shunts or valvular regurgitation at the site of or adjacent to the site of a prosthetic patch or a prosthetic device

Etiology: What Gram (+) bacterial genera are of interest in endodontics?

*-Streptococcus* -Peptostreptococcus *-Enterococcus* *-Lactobacillus* -Eubacterium *-Actinomyces*

Radiographic Examination: What are the 14 specific recommendations of the current AAE/AAOMR paper on the use of CBCT in Endodontics?

*1. Intraoral radiographs should be considered the imaging modality of choice in the evaluation of the endodontic patient. (Diagnosis). ABE likes this one.* 2. Limited FOV CBCT should be considered the imaging modality of choice for diagnosis in patients who present with contradictory or nonspecific clinical signs and symptoms associated with untreated or previously endodontically treated teeth. (Diagnosis) 3. Limited FOV CBCT should be considered the imaging modality of choice for teeth with suspected extra canals, complex morphology, or dental anomalies. (Initial Treatment) 4. Limited FOV CBCT should be considered intra-appointment for identification and localization of calcified canals. (Initial Treatment) *5. Intraoral radiographs should be considered the imaging modality of choice for immediate postoperative imaging. (Initial Treatment) ABE likes this one too.* 6. Limited FOV CBCT should be the imaging modality of choice for VRF if the clinical exam and 2D radiographs are inconclusive. (ReTx) 7. L FOV CBCT should be the imaging modality of choice when evaluating non-healing of previously treated teeth. (ReTx) 8. L FOV CBCT should be the imaging modality of choice for retreament to assess any possible complications. (ReTx) 9. L FOV CBCT should be the imaging modality of choice for all pre-surgical Treatment planning. (Surgical ReTx) 10. Special Conditions: L FOV CBCT should be the imaging modality of choice for the placement of implants. 11. Special Conditions: L FOV CBCT should be the imaging modality of choice for Dx and management of traumatic injuries in the absence of other maxillofacial or soft tissue injury that may require other advanced imaging modalities. 12. Special Conditions: L FOV CBCT should be the imaging modality of choice for localizing and differentiating resorptive defects. 13. Intraoral radiographs should be considered the imaging modality of choice for evaluating healing following NS and Surgical RCT (Outcome assessment) 14. If CBCT was the initial imaging modality of choice, and the patient has no signs/symptoms following treatment, it may be the imaging modality of choice to assess post-operative healing. If there are signs and symptoms, a CBCT is indicated. (Outcome Assessment)

Root Canal Anatomy: Maxillary 1st Molar

- MB Root: 1 canal at apex 52%, 2 canals 48% (Pineda & Kuttler); 71% had 2 canals (Fogel) - DB Root: 1 canal at apex 96%, 2 canals 4% (Pineda & Kuttler) - P Root: 1 canal at apex 100% (Pineda & Kuttler)

Radiographic Examination: What is the AAE's current general recommendations for the use of CBCT in Endodontics?

1. CBCT should be used only when the patient's history and a clinical examination demonstrate that the benefits to the patient outweigh the potential risks. 2. CBCT should not be used routinely for endodontic diagnosis 3. CBCT should not be used routinely for screening purposes in the absence of clinical signs and symptoms. 4. CBCT should only be used when th ended for imaging cannot be met by lower dose 2D radiography

Application of Biologic Principles: How does calcium hydroxide work? References? Why do you use calcium hydroxide in the avulsed tooth? What are some other uses of calcium hydroxide? What is the pH of Ca(OH)2?

*How does it work?* Several theories: 1. CaOH has osteogenic potential 2. The alkaline phosphatase which favors calcification instead of acid phosphatase which is present in resorption 3. CaOH is antimicrobial 4. The small particle size may stimulate calcification 5. Ca from CaOH may actively participate in the hard tissue formation. *References:* -Tronstad (1981) Diffusion of CaOH ions occurs through the dentinal tubules causing an increase in pH thereby influencing the resorptive processes at the root surface. -Hasselgren and Cvek (1988): long term (12 days) of CaOH can dissolve necrotic tissue, and CaOH enhanced the tissue dissolving effects of NaOCL -Siqueira & Lopes (1999) - Ca(OH)2 is a strong alkaline substance (pH = 12.5) and most endodontopathogens are unable to survive in the highly alkaline environment. Antimicrobial activity of Ca(OH)2 is related to the release of hydroxyl ions which may: 1) damage the bacterial cytoplasmic membrane 2) cause protein denaturation 3) damage to the DNA. Killing of bacteria by Ca(OH)2 will depend on the availability of hydroxyl ions in solution to retain a very high pH. Certain bacteria, such as enterococci, tolerate very high pH values, varying fro 9 to 11. If Ca(OH)2 needs to diffuse to tissues and the hydroxyl concentration is decreased as a result of the action of buffering systems (bicarbonate and phosphate), acids, proteins, and carbon dioxide, its antibacterial effectiveness may be reduced or impeded. There are many studies to support or refute Ca(OH)2's ability to diffuse into tubules to kill bacteria. Bacteria may survive after intracanal medication for several reasons: 1) they may be intrinsically resistant to the medication 2) bacterial cells may be enclosed within anatomical variations inaccessible to the medication 3) medication may be neutralized by tissue components and by bacterial cells or products 4) medication may remain in the canal for insufficient to reach and kill the bacterial cells 5) bacteria may alter their pattern of gene expression after changes in the environmental conditions. Ca(OH)2 also acts as a physical barrier to protect against bacterial penetration and kill remaining microorganisms by withholding substrate for growth and by limiting space for multiplication

Treatment: What is a decoronation procedure, and how is it done?

*Malmgren* recommended decoronation of the ankylosed tooth due to replacement resorption once infrapositioning greater than 1mm is noticed. 1. Decoronate the tooth and use the crown to act as a provisional. 2. Surgical Flap 3. Removal of previous root canal materials 4. Reduce tooth to below the level of the alveolar ridge. 5. Close surgical site, primary closure desirable. 6. Observe

Treatment: If that periapical lesion is a cyst, will it heal with NSRCT?

*Patterson* suggests that it will respond to NSRCT, as only 12% of the teeth in his study required periapical surgery. As 84% of those teeth had granulomas, you have to assume that they respond to non-surgical treatment. Lalonde confirms this with a study that has a large sample size. He noted that larger lesions (16+mm in diameter) trended significantly towards cysts. Morse also suggests that a cyst will respond to NSRCT (82% success rate)

Treatment: How should you use irrigation close to your working length?

*Sedgley* states that larger volumes of irrigant applied at the working length allows for more mechanical removal of bacteria.

Treatment: You are fan of 2-appointment NSRCT, with an interim medicament of calcium hydroxide. Can you cite any authors that will support your decision? Sjogren, Figdor, Persson & Sundqvist (1997)-role of canal infection on the prognosis of NSRCT

*Sjogren & Sundqvist* (1997) demonstrated a 94% healing rate of infected periapical lesions when a negative culture was attained, whereas there was only a 68% success rate in the presence of a positive culture. They therefore advocated the use of intracanal medicaments to maximize the removal of bacterial contaminants. *The study itself* All canals initially infected and had periapical lesion. After chemomechanical debridement 94% of negative cultures healed and 68% of positive cultures healed. Supports 2 appt NSRCT and the use of antimicrobial intracanal medicaments. (Used 0.5% NaOCl)

Treatment: What type of flap do you use for periapical surgery? Who has compared how various flaps heal after surgery? What were their results?

*Von Arx* (2007) intrasulcular incision technique had more recession of gingival margin and greater attachement loss than papilla-based incision and submarginal incision techniques.

Etiology: What are the genera of Gram Positive bacteria?

- *Streptococcus* - Peptostreptococcus - *Enterococcus* - Lactobacillus - Eubacterium - *Actinomyces*

Root Canal Anatomy: Mandibular Canine

- 1 Canal at apex 95% (Pineda & Kuttler) -2 Canals at apex 5% (Pineda & Kuttler) -6% have 2 foramina (Vertucci) -16% have Weine Type II or Type III Canals (Vertucci)

Root Canal Anatomy: Mandibular Central Incisor

- 1 Canal at apex 98% (Pineda & Kuttler) -2 Canals at apex 2% (Pineda & Kuttler) - 3% have 2 foramina (Vertucci) -27% Weine Type II or Type III Canals (Vertucci)

Root Canal Anatomy: Mandibular Lateral Incisor

- 1 Canal at apex 99% (Pineda & Kuttler) - 2 Canals at apex 1% (Pineda & Kuttler) -2% have 2 foramina (Vertucci) -23% have Weine Type II or Type III (Vertucci)

Root Canal Anatomy: Mandibular 2nd Premolar

- 1 Canal at apex 99% (Pineda & Kuttler); 85% (Zillich & Dowson) - 2 Canals at apex 1% (Pineda & Kuttler); 12% (Zillich & Dowson) -<3% will bifurcate (Vertucci) -48% have lateral canals in the apical third (Vertucci) -85% laterally positioned foramen

Root Canal Anatomy: Maxillary 1st Premolar

- 2 roots 57% of the time (Vertucci) - 2 Canals 87% of the time (Vertucci) - 1 Canal at apex 50% (Pineda & Kuttler) - 2 Canals at apex 49% (Pineda & Kuttler); 69% (Vertucci) - 3 Canals at apex 1% (Pineda & Kuttler) -Foramen located laterally 88% of the time (Vertucci)

Pathogenesis: What are the primary facial spaces germane to endodontic infections?

- Buccal Vestibule: Buccinator muscle and alveolar mucosa. Teeth involved: posterior teeth with root apices inferior to the buccal insertion (maxillary) or superior to the buccal insertion (mandibular) - Buccal Space: Buccinator muscle and the cheek mucosa. Teeth involved: posterior teeth with root apices Superior to the buccal insertion (maxillary) or inferior to the buccal insertion (mandibular). *NOTE: buccal space infections can spread to the periorbital space due to close proximity - Pterygomandibular Space: Medial Pterygoid muscle and the mandibular ramus that is inferior to the lateral pterygoid muscle. Teeth involved: mandibular second or third molars. - Canine Space: Superior to the levator anguli oris muscle and inferior to the levator labii superioris. Teeth involved: Maxillary canines and first premolars with infection breaking through the buccal cortex. - Periorbital Space: Deep to the orbicularis occuli. Teeth involved: maxillary canines or an enlarged buccal space infection. - Submandibular Space: - Submental Space: - Mental Space: - Sublingual Space:

Etiology: What are the genera of Gram Negative bacteria?

- Fusobacterium - Treponema - *Prevotella* - *Porphyromonas* - Tannerella - Dialister - Campylobacter - Veillonella

Biological Principles: What techniques can you use to remove the smear layer? Is it important to remove the smear layer?

- Madison & Krell (1984): indicated that removal of the smear layer had no adverse effects on the integrity of the apical seal. - Drake (1994) claimed that removing the smear layer allowed more bacteria to penetrate the dentinal tubules. His is the only significant study to advocate leaving the smear layer. (I personally disagree with it- the smear layer is created by the endodontist, and should therefore be removed by the endodontist. The smear layer is being created as the environment is changing, and there is a net reduction in bacteria as this is happening. The odds of a significant amount of bacteria entering the dentinal tubules as a result of removing the smear layer is minimal in my opinion) - Sen, Weeselink, & Turkin 1995: Definitive article reviewing 10 points of the smear layer. They recommended removal. -McComb & Smith (1975): First to describe the smear layer. Recommended NaOCl for organic debris and EDTA for removal of the smear layer and hard tissues. - Yamada: Recommended smear layer removal with 17% EDTA, followed by full-strength NaOCl. Always finish with NaOCl - Foster: Removal of the smear layer allows calcium hydroxide to penetrate the tubules more. - Saleh: Removal of the smear layer allows sealer to penetrate the tubules, creating a better apical seal.

Etiology: What are the three primary molecular techniques used to discover or identify bacteria?

- PCR: Polymerase Chain Reaction - FISH: fluorescent in situ hybridization - DNA Checkerboard Analysis

Biological Principles: What type and concentration of irrigant do you use? What other types of irrigants are used?

- Peters (2005) indicated that liquids are better at lubricating the canal when compared with paste-type chelators. - When I start with my glide path files, I will typically use a paste-type chelator (Glyde, etc.), but once the canals are opened initially, I switch to full-strength NaOCl (8.25%). Cullen et.al. (2015) demonstrated that 8.25% is safe when used with the established precautions (side-vented needle, no binding), and that there is a significant decrease in pulp dissolution time. As the substantivity is still poor (Cullen), I irrigate frequently with NaOCl. Shih & Rosen (1970) indicated that full-strength NaOCl gave immediate sterilizing effects, although complete sterilization was not achieved). Harrison, Svec, and Baumgartner (1978): Full-strength NaOCl did not increase the incidence of post-op pain. Harrison & Hand (1978): diluting NaOCl reduces the ability to dissolve necrotic tissue. - I also use 17% EDTA to remove the smear layer (Yamada 1983) - 2% CHX gel can be used in place of calcium hydroxide if e. Faecalis is suspected. (Dametto 2005). Rosenthal (2004) recommended CHX just prior to obturation due to its excellent substantivity (up to 12 weeks)

Pathogenesis: What is the general bacterial composition of primary and secondary infections?

- Primary Infections: equal number of Gram (+) and Gram (-) species, with more anaerobes than aerobes - Secondary infections: varying ratios of Gram (+) to Gram (-) species, with an equal number of anaerobes and facultative species.

Treatment: Why would you choose to go with a larger apical prep size?

- Senia (1971): a larger apical prep size increased the amount of tissue removal, thus reducing the amount of bacteria from the canal - Card (2002): a larger apical prep size reduces the bacteria count - Falk (2005): a larger apical prep size facilitates better irrigation at 1mm - McGurkin-Smith (2005): larger prep size, irrigation with EDTA/NaOCl and the use of calcium hydroxide for at least one weak dramatically reduces the bacterial count.

Pathogenesis: What malignancies of the jaw are known to cause radiographic changes?

- Squamous Cell Carcinoma - Osteosarcoma - Multiple Myeloma - Non-Hodgkin Lymphoma - Metastatic Cancers

Medical History: What are the signs of stroke?

- Sudden numbness or weakness in the face, arm, or leg, especially on one side of the body. - Sudden confusion, trouble speaking, or difficulty understanding speech. -Sudden trouble seeing in one or both eyes. -Sudden trouble walking, dizziness, loss of balance, or lack of coordination. -Sudden severe headache with no known cause

Prognosis: How does the presence of a separated instrument affect the long term prognosis of a case?

-*Crump and Natkin*, (1970)-No diff in broken/non-broken instr or vital/necrotic pulp on success in 53 matched pairs; depends on location and degree of debridement before fx instr - *Fox & Moodnik* confirm Crump & Natkin. -Saunders (2004)-no diff in fx/not fx instr in bacterial leakage -Spilli et al (2005)-Incidence 3.3%-5% but did not impact success Ino diff) -Souter (2005)-files rem in apical and middle third sig weakened teeth, try to bypass and incorporate in filling -Iqbal (2006)-platforms

Treatment: 1 vs 2 appointments:

-*Molander* et al (2007): No diff in 1 vs 2 appt for complete healing (65%/75%) -*Figini* et al (2008) meta-analysis: No diff in 1 vs 2 appt -*Eleazor* (1998) Retrospective study: Flare-ups 1 appt (3%) < 2 appts (8%) -*Bystrom* (1985) C&S (20-43% complete disinfection), + NaOCl (40-60%), + 24hrs CaOH (90%), + 7 days CaOH (100%)

Root Canal Anatomy: Mandibular 1st Premolar

-1 Canal at apex 74% (Pineda & Kuttler); 69% (Zillich & Dowson); 76% (Baisden) - 2 Canals at apex 25% (Pineda & Kuttler); 23% (Zillich & Dowson); 24% (Baisden); 33% of the Black population vs. 14% of the white population - a 3x difference (Trope) - 3 Canals at apex 1% (Pineda & Kuttler) -25% will bifurcate (Vertucci) -44% have lateral canals, in the apical third (Vertucci) -32% have anastamoses in the middle third (Vertucci) -85% Laterally positioned foramen (Vertucci)

Prognosis: According to Sjogren and Sundqvist (1990), What is the effect of the apical level of obturation on healing of teeth with pulpal necrosis and PARL?

-94% healing rate: obturated less than 2mm short -76% healing rate: obturated long -68% healing rate: obturated more than 2mm short *20-25% change in prognosis if you obturate less than ideal.*

Root Canal Anatomy: Tell me about furcation canals.

-According to *Burch* (1974): *76%* of all teeth had foramina in the furcation area. -According to *Vertucci* (1974): *46%* of the teeth exhibited lateral canals in the furcation region. -Gutmann (1978) indicates that furcal periodontal disease may be rectified by endodontic treatment (elimination of furcation canals).

Biological Principles: Do you use intracanal medicaments? Which ones do you use and why?

-Bystrom 1985: leaving a canal empty can allow it to repopulate with bacteria. I use Calcium Hydroxide -Bystrom 1985: Ca(OH)2 for 1 week eliminated all traceable bacteria (Cleaning & shaping alone: 40%, w/ sodium hypochlorite 60%, with 24 hr. Ca(OH)2 90%) -Sjogren (1991): Ca(OH)2 for one week eliminates bacteria and e. faecalis. -Savafi (1993): Ca(OH)2 kills LPS (gram negative bacteria wall component) -Estrella (1999) and Chamberlain (2009): calcium hydroxide needs to touch the canal walls to be effective

Treatment: Why would you attempt to achieve a larger apical prep size?

-Card (2002) improved bacterial reduction -McGurkin-Smith (2005) larger apical prep with 5.25% NaOCl, EDTA and CaOH reduced bacteria: (remaining bacteria: access (94%), C&S w/ irrigation (53%), CaOH 1 week (14%) -Falk (2005) larger apical prep size led to better irrigation at 1 mm (#36 file: 27% bacteria, #60:10%, #77:11%) -Senia (1971) apical prep size led to better tissue removal from canal -----use larger apical prep size in necrotic cases/retreatments to get better bacteria removal

Trauma: What procedure would you perform for a traumatic pulpal exposure on a maxillary central incisor of an 8 year old with an open apex and a vital pulp? Studies? If you do an apexogenesis procedure do you always do endodontic therapy after the root maturation is completed? References?

-Cvek (1978)-Cvek( partial pulpotomy) pulpotomy. Remove coronal 2mm of pulp (if bleeding stop) and place MTA or Dycal; 2 mm depth of prep justified by Cvek, who found only 2.2mm of inflammation into pulp after pulps exposed for 168 hours -Fuks- 94% success of partial pulpotomy -Witherspoon (2006)-MTA pulpotomy success was 95% -Cvek & Lundberg (1983)-not need to do pulpal extirpation following pulpotomy; 16/21 teeth had normal pulp tissue histologically

Radiographic Examination: List the uses of taking angled radiographs during endodontic diagnosis and treatment (according to Fava et al 1997)

-Determining: 1. the number of canals 2. location of canals 3. shape of canals 4. size of canals 5. direction of curvature of roots and canals 6. superimposed roots and canals -Locating the position of root apices in relation to anatomical landmarks - Distinguishing between internal and external root resorption -locating foreign bodies following trauma -establishing the position of root fractures or resorptive processes.

Root Canal Anatomy: Maxillary 2nd Molar

-MB Root: 1 canal at apex 73%, 2 canals 27% (Pineda & Kuttler) -DB Root: 1 canal at apex 100% (Pineda & Kuttler) -P Root: 1 canal at apex 100% (Pineda & Kuttler)

Root Canal Anatomy: Mandibular 2nd Molar

-Mesial Root: 1 canal at apex 79%, 2 canals at apex 21% (Pineda & Kuttler) - Distal Root: 1 Canal at apex 97%, 2 Canals 3% (Pineda & Kuttler) -81% had 3 canals (Weine) -11% had 4 canals (Weine)

Root Canal Anatomy: Mandibular 1st Molar

-Most common endodontically treated tooth (Vertucci) Mesial Root: 1 Canal at apex 43%, 2 Canals 57% (Pineda & Kuttler) Distal Root: 1 Canal at apex 86%, 2 Canals 14% (Pineda & Kuttler) -65% had 3 canals (Skidmore) -28% had 4 canals (Skidmore) -7% had 2 canals (Skidmore) -46% had a lateral canal in the furcation area (Vertucci)

Anatomy: what are the components of the dental pulp?

-Odontoblasts -Fibroblasts -Vascular structures -Immune cells and lymphatics -Nerves -extra-cellular connective tissue.

Prognosis: According to Sjogren and Sundqvist (1990), What are the success rates for initial therapy?

-Overall Success Rate: 91% -Vital Cases: 96% -Non-vital Cases w/o PARL: 100% -Non-vital Cases w/ PARL: 86%

Prognosis: According to Sjogren and Sundqvist (1990), What are the success rates for retreatment?

-Previously Treated w/o PARL: 98% -Previously Treated w/ PARL: 62%

Root Canal Anatomy: Maxillary 2nd Premolar

-Second most common endodontically treated tooth. (Vertucci) - 1 canal at apex 75% (Vertucci); 82% (Pineda & Kuttler) - 2 canals at apex 24% (Vertucci); 18% (Pineda & Kuttler) - 3 canals at apex 1% (Vertucci); 0% (Pineda & Kuttler)

Prognosis: How do Positive/Negative Cultures affect the prognosis of an endodontically treated tooth?

-Seltzer and Bender (1963): No difference (84% vs 81%) -Sjogren et al (1997): 94% neg cultures healed, 68% of positive cultures healed -Molander et al (2007) Neg samples 80% success, positive sample 49%

What degree of bevel do you place the root end on during apical surgery? Why is the degree of the bevel important? Do you always perform an apicoectomy?

-Try to place minimal bevel that is manageable for vision and access. -Aim for 3 mm resection -Angle should be minimized to prevent apical leakage from dentinal tubules -Vertucci (1986): Must do a root end filling since patent dentinal tubules allow apical leakage under root end filling w/45 degree bevel -Gilheany (1994): 0 degree bevel needs 1 mm filling, 30 degrees needs 2.1 mm, 45 degrees needs 2.5 mm -Kim (2001): 3 mm resection with 0 degree bevel remove apical ramification/lateral canals (98%/93%), 2mm resection (76%/86%), 1 mm resection (52%/40%) Apicoectomy (root end resection) always performed due to presence of isthmuses which may be cause of failure. Cambruzzi and Marshall (1983): MB root max molars (30%), M root man molar (60%), D root man molar (15%) Weller (1995)-100% of MB roots had full or partial isthmus at 4 mm level (so prep all root between 2 canals) Von Arx-isthmus presence: MB root 76%, M root 83%, D root 36%

Treatment: What are the components and properties of Cavit?

-Zinc Oxide -Calcium Sulfate -Zinc Sulfate -Glycol Acetate -Polyvinyl Acetate -Triethanolamine -Red Pigment Cavit is hydroscopic, expanding when wet (thus providing an excellent initial seal, though poor compressive strength.) Because of this characteristic, Cavit should never be used on a vital tooth, or as a temporary cement for crowns.

Anatomy: what is the average distance between the major foramen and the anatomic apex?

0.9mm according to a CBCT study by El Ayouti

Treatment: What are the factors that affect flap design for endodontic apical surgery?

1. Amount of attached gingiva 2. Number of teeth involved 3. Depth of periodontal pockets 4. Length of the roots involved 5. Amount of access needed 6. Presence of pathosis 7. Dimensions of the pathosis 8. Presence of anatomic structures 9. Esthetic considerations 10. Patient factors

Diagnosis: What leads to the successful diagnosis of orofacial pain, according to Drinnan?

1. An accurate and detailed history of the pain. 2. A detailed clinical examination. 3. A thorough knowledge of those conditions that may produce facial pain.

Complications of Treatment: What are the two main factors associated with a sodium hypochlorite accident?

1. An open apex 2. extreme pressure during irrigation

Treatment: Describe the effectiveness of four clinical irrigation methods on the removal of root canal debris, as described by Abou-Rass (1982).

1) proximity of the needle to the apex is an important role in irrigation (the needle must come close to the material it is going to remove). 2) A 30 gauge needle is more effective than a 23 gauge needle. 3) Narrow canals prepared to at least a size #25 can be effectively flushed if sufficient taper of the canal exists. 4) The use of alternating solutions of H2O2 and NaOCl was no more effective than other methods tested.

Pathogenesis: What are the three primary virulence factors of E. faecalis?

1. (Love) Ability to invade dentinal tubules and bind to collagen in the presence of human serum. (Type I Collagen, which is found in dentin). 2. (Evans) The proton pump found in E. Faecalis is one of the main factors in it's ability to withstand the high pH effects of Calcium Hydroxide. 3. (Sedgley) Ability for E. Faecalis to survive and recover from prolonged starvation (studied up to 12 months). These three points are summarized beautifully by Stuart (2006)

Treatment: What are the advantages of utilizing a microscope in endodontics?

1. Aids in the location of normal anatomical structures. 2. Detections of cracks or fractures. 3. Removal of obstructions. 4. Management of complications. 2012 AAE Position statement: the microscope is an integral and important part of the performance of modern endodontic techniques.

Complications of treatment: What are Seltzer's 7 etiological factors for Flare-ups in Endodontics?

1. Alteration of the local adaptation syndrome (disrupting the chronic inflammation). Seyle 1953 2. Changes in periapical tissue pressure (Mohorn 1971) 3. Microbial Factors (Sundqvist 1976) 4. Effects of chemical mediators 5. Changes in cyclic nucleotides 6. Immunological phenomena 7. Psychological factors

Application of Biologic Principles: What are the commonly reported properties of eugenol?

1. Alters neurotransmission by increasing potassium permeability and decreasing sodium influx, thus reducing the action potential. (Kozam) 2. Blocks the expression of neuropeptides (Trowbridge) 3. Decreases the vascular response to epinephrine. (Mjor)

Application of Biologic Principles: According to Harrison, what are the progressive stages of healing?

1. Clotting & Inflammation 2. Epithelial Healing 3. Connective Tissue Healing 4. Maturation 5. Remodeling

What are the 5 Biological objectives of a root canal, according to Schilder (1974)?

1. Confine instrumentation to the root canals (don't repeatedly instrument beyond the apex) 2. Beware of forcing material beyond the apical foramen 3. Remove all tissue debris from the root canal system 4. Complete cleaning and shaping of single canals in one visit (to prevent flare-ups) 5. Create sufficient space during root canal enlargement for intracanal medicaments and for potential exudate reception

Treatment: What are the 5 shaping objectives according to Schilder (1974)?

1. Continuous taper 2. The cross-sectional diameter of the prep should be narrower at every point apically 3. The prep should flow with the 3D shape of the original canal 4. The apical foramen should remain in its original spatial relationship 5. The apical opening should be kept as small as is practical in all cases.

Physiology: What are the common changes seen in pulp tissue with aging?

1. Decrease in the number of nerves and blood vessels. 2. Increase in fibrosis. 3. Increase in cementum and predentin width. 4. Increase in diameter of the major apical foramen. 5. Change in the position of the major foramen with respect to the anatomical apex. (Note the minor foramen remains contstant).

Treatment: What are the general purposes for coronal flaring?

1. Decrease the incidence of rotary separation 2. Provide straight-line access to the apical third of the canal. 3. Allow for the apical foramen to be reached more consistently with EALs.

Treatment: What are the steps for treating a Phoenix Abscess?

1. Diagnosis 2. Complete pulpectomy 3. Needle aspiration of purulent exudate through soft tissues 4. Incision and Drainage 5. Abx if indicated

Treatment: What are the properties of sodium hypochlorite that make it an effective canal irrigant?

1. Dissolves necrotic tissue (*Baumgartner*) 2. Dissolves vital tissue (Rosenfeld) 3. Kills planktonic bacteria (Haapasalo) 4. Kills bacteria in established biolfilms (Del Carpio) 5. Kills bacteria in dentinal tubules (Wong)

Diagnosis: According to Jaeger, what are the 4 theories of referred pain mechanism?

1. Efferent sympathetic impulses lead to a local vasoconstriction, leading to ischemia and compromised nutritional supply. 2. the branded primary afferent hypothesis, where a single primary afferent branches to supply both a deeper structure and the structure in which pain is perceived 3. the convergence-projection hypothesis of referred pain (most popular theory): visceral afferent nociceptors converge onto the same pain-projection neurons as the afferents from the somatic structures feeling the pain 4. The Convergence-Facilitation Theory (similar to the convergence theory): the impulses facilitate second-order neuron transmission, which is usually created by the somatic afferents.

Radiographic Examination: What are the advantages of CBCT over traditional 2D radiographs?

1. Eliminates anatomical noise. 2. Eliminates geometric distortion 3. You only need one image (remember Brynolf's recommendation for multiple images, 1970) 4. Increased ability (sensitivity) to detect periapical pathology — Patel (2009): CBCT could detect lesions that were confined to cancellous bone. — Remember that Seltzer and Bender (1961) indicated that the cortical plate needed to be breached before a PARL lesion could be viewed radiographically

Medical History: What are the complications that can arise from the long-term use of anti-platelet drugs (ASA, NSAIDs)?

1. Excessive bleeding 2. Gastrointestinal bleeding 3. Tinnitus 4. Bronchospasm

Medical History: What are the four major types of Lymphomas?

1. Hodgkin's 2. Non-Hodgkin's 3. Burkitt's 4. Multiple Myeloma

Complications of Treatment: Your patient has an asthma attack. What do you do?

1. If in the middle of treatment, suction out irrigation and remove the rubber dam. 2. Sit the patient up. 3. Administer a fast-acting bronchodilator (β₂ agonist - albuterol) 4. If needed, administer 0.3-0.5ml of subcutaneous epi. 5. Activate EMS 6. Repeat subcutaneous epi every 5 minutes until EMS arrives.

Radiographic interpretation: What are the three primary results of collimation?

1. Increased patient safety. The lined collimator absorbs stray photons, thus refining the area of patient exposure to the desired area of visualization. 2. Increases the image quality by reducing the amount of scattered radiation. 3. Collimation reduces the beam size, leading to more parallel photons and therefore a sharper image.

Radiographic Examination: What are the major disadvantages of CBCT?

1. Increased radiation doses 2. Substantial cost of the machine 3. Scans take 20-40 seconds, which predisposes the images to movement distortion. This is a no-go for patients who can't hold still. 4. Bone can be difficult to differentiate from dentin 5. Limited spatial resolution: lesion must be greater than 1.4mm in diameter for adequate detection (According to Tsai) 6. Beam hardening secondary to metallic restorations can render the image non-diagnostic 7. Liability risk for non-diagnosis of non-dental structures.

Treatment: What are the three primary factors that influence a practitioner who deciding between single and multiple-visit endo?

1. Influence on Prognosis 2. Capacity to Disinfect 3. Effect on Post-treatment pain Advocates for Calcium Hydroxide and 2-Visit Endo: - *Sjogren* (UltraCal needs 7 days of treatment) - *Law & Messer* (more undetectable bacteria w/ use of UltraCal) Advocates for single visit endo: - *Peters & Wesselink* - Vera - *Roane* (more post-op pain w/ mult. visit endo)

Pathogenesis: Name the categories of Resorption

1. Internal Root Resorption 2. Invasive Cervical Root Resorption 3. External Inflammatory Root Resorption 4. Replacement Resorption 5. Pressure Resorption

Medical History: What are the common complications of Diabetes Mellitus?

1. Ketoacidosis 2. non-ketotic coma 3. Retinopathy/blindness 4. Accelerated atherosclerosis 5. Ulceration and gangrene of feet 6. Neuropathy 7. Early Death

Treatment: What are the basic principles of flap design?

1. Maintain maximum blood supply. 2. Place lines of incision over sound bone. 3. Insure adequate size. 4. Avoid sharp corners. 5. Avoid incision over bony eminence. 6. Insure proper placement of horizontal incision. 7. Use care in retracting and handling tissues. 8. Carefully analyze periodontal condition

Pathogenesis: What are the 4 properties attributed to E. faecalis that increase its resistance to endodontic procedures?

1. May form a biofilm (resolved with mechanical debridement) 2. Can enter dentinal tubules (resolved by irrigation reaching the dentinal tubules) 3. Possesses a proton pump (useless against CHX, but effective against CH). 4. Can survive starvation (resolved with a good endodontic seal, thus "entombing" the bacteria)

Application of Biologic Principles: What are the 7 common antibiotics used to treat endodontic infections?

1. Penicillin VK 2. Amoxicillin 3. Augmentin 4. Cephalexin 5. Clindamycin 6. Azithromycin 7. Metronidazole

Complications of Treatment: Your patient experiences post-operative swelling after a root canal. What is your differential diagnosis?

1. Post-op Flare Up 2. Necrotizing Fasciitis 3. Allergic Reactions 4. Angioedema 5. Hematoma 6. Air Emphysema

Medical History: What are the three primary ways that dental procedures can harm a fetus?

1. Radiation (but it would take a lot) 2. Drugs 3. Stress

Treatment: When do you use ultrasonics?

1. Simon 1993: C-shaped canals 2. Metzler & Montgomery: 1-appointment cases 3. Moorer 1982: ReTx or necrotic cases - Cunningham & Martin 1982: Ultrasonics and high volume irrigation combined were better than conventional methods alone. - Haidet 1989: ultrasonics improved cleaning at 1mm level as well as in isthmuses. - Moorer 1982: agitating NaOCl improved its effectiveness

Medical History: Your patient has asthma. What measures will you take to prevent an asthma attack in your office?

1. Take a good medical history 2. Avoid precipitating factors 3. Medical consult for severe asthmatics 4. Avoid ASA, NSAID, Narcotics, Barbituates 5. In rare cases you may need to avoid anesthetics containing sulfites (preservatives for epi). 6. Provide a stress-free environment 7. Use nitrous as needed 8. Use a pulse oximeter 9. Recognize the signs/symptoms of an attack

Medical History: What are the potential problems related to a patient with end-stage renal disease?

1. Tendency to bleed 2. HTN 3. Anemia 4. Intolerance to nephrotoxic drugs metabolized by the kidney 5. Enhanced susceptibility to Infection

Application of Biologic Principles: What are the top two reasons antibiotics are prescribed incorrectly?

1. The Abx prescribed is not appropriate for the culture of bacteria being treated. 2. The provider does not know how to properly treat the situation.

Pathogenesis: What are the main historical viewpoints on the progression of infection and immunology:

1. The Theory of Anachoresis - Based on the work of Gier & Mitchell - Blood-borne bacteria are attracted to areas of chronic inflammation -Delivanis debunked the theory with his testing with cats that were given hollow root canals and IV injected with bacteria. The bacteria did not localize to the chronically inflamed root canal. 2. The Focal Infection Theory - Based on the work of Westin Price - The opposite of anachoresis, the nidus of infection spreads systemically - Price's methods and outcomes were refuted by Easlick. - Zones of Fish 3. Hollow Tube Theory - Based on the work of Rickert and Dixon - Hollow tubes contained within the body (like a root canal space) collect circulatory elements and permit inflammation. - Debunked by Torneck & Wenger

Diagnosis: According to Okeson and Falace, what are the various sources of non-odontogenic toothache?

1. Toothache of myofascial origin. 2. Toothache of neurovascular origin. 3. Toothache of cardiac origin. 4. Toothache of neuropathic origin. 5. Toothache of maxillary sinus or nasal mucosa origin. 6. Toothache of psychogenic origin

Prognosis: What are the most commonly cited factors influencing the reported outcomes of surgical root canal therapy?

1. Ultrasonic vs. bur preparation 2. Magnification 3. Retrofill Material 4. Periodontal Status 5. Initial vs. Revision Surgery

Treatment: According to Schilder, what are 8 principles common to all root canal preparations as of 1974?

1. Use of abundant irrigant 2. Never skip instruments in series 3. Never change to next instrument until the present one fits loosely 4. If a file appears too large consider cutting off the tip of the previous one 1-2 mm (With stainless steel files) 5. The more curved & narrow the canal, the more it must be shaped with files in its apical end 6. Discard any instrument showing signs of unraveling 7. If you lose patency, don't panic - its probably dentin mud (Put a "helicopter" bend in the file, use EDTA, feel for a stick, irrigate) 8. Partially calcified canals may be successfully negotiated if they are treated at the outset as if they were packed with dentin mud.

Etiology: According to Morse, what are the three key things that would tell you whether or not NSRCT would be susceptible to failure?

1. Virulence of the bacteria involved. 2. Population size of the bacteria involved. 3. Host Response to the bacteria involved.

Application of Biologic Principles: According to Malamed, when should vasoconstrictors be avoided?

1. When BP is > 200/115 2. Uncontrolled hyperthyroidism 3. Patients with sever cardiovascular disease NOTE: children should be given anesthetic WITH a vasoconstrictor.

Medical History: your patient is a hemophiliac. What precautions do you need to take?

1. You must get a medical consult 2. You may need to use a Factor VIII replacement to reduce bleeding. 3. Avoid ASA and NSAIDS These are the same recommendations for patients with von Willebrand's Disease.

Prognosis: What do Salehrabi & Rotstein (2004) say about endodontic treatment outcomes in their larger epidemiological study? What is the general conclusion that can be reached from this study?

1.12 million patients in survey with 1.46 million NSRCT completed. Overall, at the end of the 8-year observation, 97.1% of the teeth were retained in the oral cavity. 97.43% of anterior teeth, 97.32% of premolars, and 96.89% of molar teeth were retained. Of the teeth extracted, 85% had no full coronal coverage. General Conclusion: Root canals with full coverage restorations survive 99.6% of the time. *Note this is SURVIVAL, not SUCCESS.*

Treatment: How long does it take for a sinus tract to heal following root canal debridement?

According to McWalter: 5-14 days

Medical history: What is the concern with taking ASA in the third trimester?

Postpartum hemorrhage and constriction of the ductus arteriosus.

Radiographic Interpretation: Who discovered the amazing properties of cathode rays, and what year were they discovered in?

1895 by Professor Wilhelm Konrad Roentgen Dr. Otto Walkoff took the first dental radiograph (in his own mouth) just 14 days later.

Radiographic Examination: According to Soh et al (1993), what is the percentage of radiation reduction when comparing digital radiographs with traditional film?

22%

Radiographic Interpretation: what is the ratio of mineralization between cortical and cancellous bone?

25:1

Trauma: According to the AAE guidelines for a tooth with a mature apex, what is the length of time a tooth can go with a lack of response to vitality testing before it is deemed necrotic?

3 months.

Application of Biologic Principles: What is the percentage of calcium hydroxide found in UltraCal?

35% Ca(OH)₂ Compare with DyCal: 25% Ca(OH)₂

Treatment: According to DeCleen, how much gutta percha should be left in the canal when preparing for a post?

3mm absolute minimum. Ideally 6mm or more is preferable.

Radiographic Exam: Rud and Ommell stated that fracture lines could only be visualized by traditional radiographs if the beam was within [BLANK] of the fracture plane.

4 Degrees

Pathogenesis: According to Stern, what is the cellular composition of the human periapical granuloma?

49% Inflammatory cells, 40% Fibroblasts, 6% vascular spaces, 5% epithelium. *Of the Inflammatory cells: -47% macrophages -32% lymphocytes -13% Plasma Cells -8% Neutrophils*

Radiographic Interpretation: What is the normal range of mA for dental radiography?

5-15mA Increased mA leads to an increase in the amount (quantity) of photons produced. mA are always related to exposure time. A higher mA translates to more photons produced at once. By controlling both mA and time, the density of the image can be controlled.

Prognosis: According to Reader, what is the success rate of pulpal anesthesia after an IA block on a mandibular first molar?

53% for first molars 61% for the first premolar 35% for the lateral incisor The author strongly advocates for IO injections.

Prognosis: What do Iqbal and Kim (2007) say about the survival rates of NSRCT/Crown vs. Implants in their systematic review? How does this compare to Salehrabi & Rotstein?

55 implant studies and 13 restored NSRCT studies were used to evaluate survival. No difference in survival therefore the decision to treat a tooth endodontically or with an implant should be based on factors other than the treatment outcomes. (implant survival 96%, RCT/crn 94%) Iqbal & Kim: 94% NSRCT/Crown survival Salehrabi & Rotstein: 99.6% NSRCT/Crn survival

Hierarchy of Evidence: List the Hierarchy of Evidence, from lowest level to highest

6. Expert Opinion 5. Case Series 4. Case Control 3. Cohort 2. Randomized Controlled Trial 1. Systematic Review

Treatment: What percentage of molars have furcation canals?

76% according to Burch & Hulen 28% according to Gutmann

Pathogenesis: According to Figdor, what critical mass of E. Faecalis is needed for them to survive for a prolonged period of time?

>10⁸ CFUs to maintain their viability under a poor nutrient/high pH environment.

Treatment: According to Reader, what is the overall success rate of an IO injection?

88%. This was also confirmed by Parente & Weller.

Prognosis: According to Sjogren and Sundqvist (1990), what is the effect of the level of instrumentation on the prognosis of roots with pulpal necrosis?

90% healing when instrumentation reached the apical constriction. 69% healing when instrumentation did not reach the apex. *That's a 20% swing. Get patency!*

Medical History: you are concerned about your diabetic patient. They took their insulin, but ate a "rushed" breakfast. You have a glucose monitor in your office, and you take a sample. At what point would they be considered to be in a hypoglycemic state?

A blood glucose level of less than 70mg/dL

Application of Biologic Principles: Tell me about the interaction between Ibuprofen and Acetaminophen. Can you cite any studies?

A combination of Ibuprofen (600mg) and Acetaminophen(1000mg) was more effective than ibuprofen alone, according to Menhinick. Breivik demonstrated that this combination provided superior analgesia with fewer side effects than an APAP/Codeine combination (Tylenol 3)

Diagnosis: What is the difference between a Dehiscence and a Fenestration?

A dehiscence involves the alveolar ridge, and is never found on the lingual. Fenestration is a window in the alveolus, where the root is exposed to soft tissue. According to Larato, 7.5% of all teeth have either a dehiscence or fenestration. Anterior teeth have them more commonly than posterior teeth

Etiology: What is a facultative Anaerobe?

A facultative anaerobe is an organism that makes ATP by aerobic respiration if oxygen is present, but is capable of switching to fermentation or anaerobic respiration if oxygen is absent. For endodontic consideration, this type of bacteria is ideal for infection. It prefers to be in the aerobic oral cavity, but as the canal system changes from aerobic to anaerobic, it has the ability to adapt.

Medical History: At what blood glucose level would you be considered a diabetic?

A fasting blood glucose level of 126mg/100ml A normal blood glucose level of 200mg/100ml

Medical History: What is the primary/most prevalent etiology for Diabetes mellitus?

A genetic disorder.

Diagnosis: Describe a Heithersay Class IV Invasive Cervical Root Resorption lesion.

A large lesion extending beyond the coronal third of the root.

Diagnosis: Describe a Heithersay Class III Invasive Cervical Resorption lesion.

A less-defined lesion extending into the coronal third of the root.

Pathogenesis: What is a Phoenix Abscess?

A phoenix abscess is a dental abscess that can occur immediately following root canal treatment. Another cause is due to untreated necrotic pulp (chronic apical periodontitis). It is also the result of inadequate debridement during the endodontic procedure. Risk of occurrence of a phoenix abscess is minimized by correct identification and instrumentation of the entire root canal, ensuring no missed anatomy.

Pathogenesis: What is the difference between a primary infection and a secondary infection?

A primary infection is an initial infection of necrotic tissue, and will have a larger variety of bacteria present. A secondary infection is an infection of previously treated teeth, and will typically involve fewer, albeit more virulent, bacteria.

Radiographic Examination: Corticated or sclerotic bone adjacent to a radiographic lesion is indicative of what?

A reactive process consistent slow-growing lesions.

Diagnosis: Describe a Heithersay Class I Invasive Cervical Resorption lesion.

A small, well-defined lesion localized to cervical areas and involving dentin only.

Radiographic Interpretation: How is x-radiation produced?

A target of high anatomic number and typically positive charge (anode) is hit with fast-moving electrons in a high vacuum. This produces

Diagnosis: Describe a Heithersay Class II Invasive Cervical Resorption lesion.

A well-defined lesion localized to cervical area but penetrating further into the dentin and close to the coronal pulp.

Application of Biologic Principles: Why is it a good idea to pair Abx administration with I&D (where possible)?

Abscesses and necrotic tissue, due to their poor blood supply, do not allow good distribution of the Abx, and can therefore create bacterial resistance. Draining the abscess allows for better Abx distribution by disrupting that environment and mechanically removing bacteria.

Treatment: When doing internal bleaching, should you place a base in the pulp chamber prior to placement of bleach?

Absolutely. Rotstein demonstrated that no H2O2 penetrated the CEJ when a minimum of 2mm of base material was placed at the CEJ. The thickness of the base was more critical than the type of material used.

Treatment: What's the point of pre-flaring a canal?

According to *Abou-Rass* (1982): Removing the cervical constriction and prepping the coronal and middle thirds will: - facilitate instrumentation in the apical third - reducing the possibility of ledging, debris packing, and instrument fracture. According to Stabholz: preflaring increases the tactile sense of your working length; your obturation is also much easier to accomplish.

Trauma: Can pulpal inflammation due to trauma heal in the absence of bacteria?

According to *Andreasen*, yes! *Bergenholtz* suggested microcracks in the tooth following trauma may result in bacterial ingress to the pulp space, thus leading to necrosis.

Treatment: Puff, or no puff?

According to *Augsburger* (1990): Healing will occur if canals are well obturated even if some obturation material is extruded into the periapical tissues. There is evidence that given enough time, all extruded sealer will be removed and that GP is more resistant to removal than sealer. Any Brazilian author (*Ricucci*) is likely to disagree with this statement.

Treatment: Should you culture your root canals? Why/Why not?

According to *Bender and Seltzer* (1964): Success rates after two years were the same (82%) for teeth that had positive cultures upon obturation, and teeth that had negative cultures. Sathorn's meta-analysis indicates that the reduction in bacterial load via Calcium hydroxide does not result in a higher incidence of healing when compared to single-visit cases. Bottom Line: you don't have to have a sterile canal to get good results...so culturing is not necessary in a typical NSRCT.

Treatment: How much of the apex do you want to resect in doing surgical ReTx?

According to *Block: 3mm*

Treatment: What is the normal direction of flow of dentinal fluid?

According to *Brannstrom*, it is an outward movement from the pulp due to the intrapulpal pressure (30 mmHg)

Prognosis: how do radiographs relate to success or failure of root canal treatment?

According to *Brynolf*: 93% of teeth with normal radiographs had PA inflammation histologically. Radiographic success does not correlate with histological success. According to *Walton*: Teeth with PARL: inflammation 100% Teeth with no PARL: inflammation 26% (contradicts Brynolf)

Treatment: is the use of chloroform safe for patients? For providers?

According to *Chutich*, chloroform is safe to use on patients. According to *McDonald*, chloroform can be safely handled by providers.

Complications of Treatment: How does the separation of a file affect prognosis?

According to *Crump & Natkin*: There is no significant effect of instrument breakage on case prognosis. *Fox & Moodnik* confirmed these findings. *Spili* had a large study that also confirms this. Empirically, it depends on several different factors: 1. Timing (if it happens early on, then the prognosis is worse) 2. Preoperative diagnosis (PARL worsens the prognosis) 3. Ability to bypass/remove instrument fragment. 4. Adequacy of obturation following separation 5. Presence of perforations created during attempts to remove instrument fragment.

Treatment: the latest full-strength NaOCl on the market is 8.25%. Does this pose a problem for endodontics with regards to the increased concentration?

According to *Cullen* (2015): No - increased concentration = decreased pulp dissolution time - increased concentration of NaOCl did not have a significant effect on dentin flexural strength or modulus - subtantivity remains poor.

Treatment: Mandibular premolar local infiltration - how successful is it when using 4% Articaine?

According to *Dressman*: a single infiltration was successful 87%. A second infiltration increased the success to 94%

Treatment: Apical surgery will expose dentinal tubules, which, if patent, can act as conduits for recurrent infection of the canal space. Bevels can increase the number of exposed tubules. How deep does your retro-fill need to be to counteract those exposures?

According to *Gilheany* (1994): -0° Bevel: 1.0mm restoration needed - 30° Bevel: 2.1mm restoration needed - 45° Bevel: 2.5mm restoration needed

Treatment: What are the affects of using Bupivicaine on post-operative pain?

According to *Hargreaves*, it reduces post-op pain.

Root Canal Anatomy: How often does the MB root of maxillary first molars have an MB2, and how often can it be found with a normal access?

According to *Kulild* (1990): 95% of teeth had MB2 54% were located with normal access 31% were located after careful use of a bur. Only 4.8% of the teeth studied had just one MB canal. According to Fogel: 71% of MB roots had two canals that were located and treated. 32% were Weine Class III 39% were Weine Class II 29% were Weine Class I Older patients tended towards Weine Class 1, whereas younger patients were more likely to have Weine Class II and Class III. According to *Wolcott* (2005): MB2 found in 60% of first molars. MB2 found in 35% of second molars. Found implies located and extending to its own foramen, or joining with MB1 no further than 5mm away from the apex. Large study involving 5616 maxillary molars. Failure to find and treat MB2 may contribute significantly to RCT failure.

Treatment: How long does Cavit last before leaking?

According to *Lamers: 42 days*.

Treatment: You are about to start an apicoectomy. Is it a good idea to have patient rinse with CHX first, or is it a waste of time and resources?

According to *Martin* (1987): It's a good idea. CHX resulted in a 94% reduction in recoverable bacteria at the surgical site.

Treatment: What is the role of ultrasonic irrigation?

According to *Metzler & Montgomery* (1989): Single visit endodontics with the use of ultrasonic irrigation was as effective as 2 appointment endodontics utilizing calcium hydroxide.

Treatment: Is the EAL more reliable in finding the minor constriction of the canal, or the major diameter of the apical foramen?

According to *Ounsi & Naaman*: the major diameter of the apical foramen. Clinical Relevance: when using the apex locator, take it to the major diameter (i.e. the first red line on the apex locator display). This will "calibrate" you unit, and give you a more desirable outcome.

Treatment: Is Super EBA an acceptable dental material for retro-grade restorations?

According to *Oynick & Oynick* (1978): Super EBA is biocompatible. *Note: the trend has gotten away from EBA because it's really hard to mix. Not user friendly. It gets hard very quickly. It's tacky (that's good & bad).*

Treatment: What percentage of the canal wall remains untouched by endodontic instrumentation?

According to *Peters*: 35%

Radiographic Interpretation: What are the average dimensions of the mental foramen?

According to *Phillips and Weller*: Horizontal: 4.6mm Vertical: 3.4mm Foramen is typically larger on the left side than on the right.

Radiographic Interpretation: What is the most common location for the mental foramen?

According to *Phillips and Weller*: Inferior to the crown of the second premolar (63%) -mesial to that point 1.9mm on average 18% of the time, and distal to that 2.2mm 19% on average. The average vertical distance from the buccal cusp tip of the 2nd premolar to the inferior border of the mandible was 36mm. Ave dist. from cusp tip to the mental foramen was 21.8mm (60% of the distance from cusp tip to inferior border of the mandible)

Diagnosis: T/F: referred pain from the heart can be felt in the mandible.

According to Glick: True. It can be felt in the inferior border of the mandible, typically on the left side.

Treatment: Why is the use of the microscope for apical surgeries a good thing?

According to *Rubinstein* (1997): The SOM offers the following advantages: - improved visualization of the surgical field, -idealized surgical technique, -decreased number of radiographs, -enhanced patient education, -enhanced referral communication, and -documentation for legal purposes. -Fractures, accessory canals, canal isthmuses, and fins can readily be visualized. -With the SOM, periapical curettage is facilitated, because bony margins can be scrutinized for completeness of tissue removal.

Radiographic Interpretation: How much bony destruction must there be in order for a periapical lesion to be detected on a traditional radiograph?

According to *Seltzer and Bender (1961)*, there needs to be extensive destruction and/or perforation of the cortical plate for a lesion to appear on a radiograph. Therefore, there can be a lot of cancellous bone loss before a lesion appears radiographically. This comes to play particularly in cases of symptomatic apical periodontitis or acute apical abscess.

Treatment: What is an effective way to sterilize gutta percha cones?

According to *Senia*, and confirmed by *Cardoso*: gutta percha cones may be sterilized in all cases by a one-minute immersion in full-strength NaOCl. Ludlow suggested that one second in 2.5% NaOCl was effective as well...I'd stick with one minute.

Root Canal Anatomy: Describe the root canal anatomy of Mandibular First Molars.

According to *Skidmore* (1971): Mandibular First Molars: 65% 3 canals 28% 4 canals 7% 2 canals Mesial Root: 60% Weine Class III. 40% Weine Class II. Distal Root w/ 2 Canals: 39% Weine Class III. 61% Weine Class II. Recommended more of a rectangular shaped access to locate a second distal canal. According to *Pomeranz*: Middle mesial canals occurred in 12% of teeth studied. Middle mesial is located in the danger zone of the mesial root. Theorized that The root may start with one large canal, and progress to two canals with anastamoses as the deposition of dentin continues.

Treatment: You are a fan of pulp capping. Who can you cite to support your position?

According to *Stanley* (1989): 1. You can use direct pulp caps on large exposures. In fact, in some cases the exposure should be enlarged to remove dentin chips and clean the wound, and allow adequate contact of the capping agent. 2. Contaminated pulps can be capped, as numerous studies show no difference in healing potential. 3. You can cap a previously restored tooth. 4. Older teeth can be capped, 5. Periodontally involved teeth can be capped. 6. Pulp obliteration occurs infrequently. 7. Increased resorption following pulp capping in primary teeth is due to the resorption pattern already present and not to the capping.

Application of Biologic Principles: How does placing calcium hydroxide in a canal work against external inflammatory root resorption?

According to *Tronstad* & Andreasen (1981): Diffusion of Ca(OH)2 ions occurs through the dentinal tubules causing an increase in pH thereby influencing the resorptive processes at the root surface. This diffusion from the root canal to the periphery could be beneficial by negating osteoclastic activity and by stimulating repair processes of the tissues where resorption is occurring. According to *Foster*, Kulild & Weller (1993): Removing the smear layer facilitated the diffusion of calcium hydroxide from the root canal to the exterior surface of the root.

Treatment: Apical Plugging with dentin chips. Good idea, or bad idea?

According to *Tronstad* (1978): good idea. Dentin chips create favorable healing environments and hard tissue reactions. According to *Holland* (1980): Bad idea. Dentin chips are often infected with unfavorable microbes, which led to unfavorable results. Tronstad used monkeys, Holland used dogs. Pitts (1984) showed no difference between gp/sealer and clean dentin chips in apical healing. *Himel* (1985) demonstrated that dentin chips inhibited the deposition of cementum and bone when placed at the apical foramen, and significantly more inflammation was produced compared to gp/sealer.

Treatment: When should sutures be removed following surgery?

According to *Velvart & Peters*: between 2-4 days. *Torabinejad* suggests at least 4 days due to the timeline for the proper formation of collagen fibers.

Root Canal Anatomy: Describe the root canal anatomy of mandibular Premolars.

According to *Vertucci* (1978): - 25% of mandibular 1st PM with bifurcate; - <3% of mandibular 2nd PM will bifurcate. - Lateral canals appear in 44% of 1st PMs and 48% of 2nd PMs (Apical third) Anastamoses in 32 and 30% (middle third) Lateral foramen positioning in 83-85% of PMs. According to Zillich & Dowson: Approximately 2400 mandibular PMs were examined for morphology. 1PMs: 69% 1 canal. 23% 2 canals 2PMs: 85% 1 canal. 12% 2 canals According to Weller: Man. 1st PM: 1 Canal: 76% 2 Canals: 24% C-shaped canals were found in 14% of teeth studied. Canals could be oval (51%) round (40%), C-shaped, irregular, dumbbell. According to *Trope*: Blacks had 3x more 2nd canals in mandibular first PMs than whites (33% vs. 14%) No significant difference with second PMs.

Treatment: What is a good minimum thickness for the placement of Cavit?

According to *Webber, a 3.5mm minimum thickness is recommended*. Webber conducted a study that demonstrated an average dye leakage of 2.65mm through Cavit. Therefore, a practical recommendation is 4mm, and placement of the Cavit below any compromised margin as well.

Root Canal Anatomy: Describe the root canal anatomy of Mandibular 2nd Molars.

According to *Weine* (1988): 81% of Mandibular 2nd Molars had 3 Canals. More importantly: 11% had 4 canals. So look for that 4th Canal.

Treatment: Describe the effect of orthodontic movement on apical periodontitis.

According to *de Souza* et al (2006) Orthodontic movement does not stop the healing process, although healing is faster without orthodontic movement.

Diagnosis: What does the pulp's ability to recover from injury depend on?

According to Abou-Rass (1982): 1. Type of Injury 2. duration of injury 3. thickness of remaining dentin 4. physiologic age of tooth 5. host factors 6. past trauma

Pathogenesis: What is a "stressed pulp?" What can cause a stressed pulp situation?

According to Abou-Rass: A stressed pulp is a clinical condition where a vital pulp has been subjected to repeated damage. Things that can cause a stressed pulp: Operative Procedures & Materials: - topical medications on cavity preps - continuous air drying - acidic cements - Direct Pulp Cap - deep preps - high-speed cutting w/o coolant - long-acting local anesthetic - unbased restorations - orthodontic movements - Periodontal exposure of the cementum Other Causes: - Bruxism - Caries - Perio Dz - Trauma - Attrition - Erosion - Cracks - Radiation tx - Systemic Diseases - Diabetes - Vit. C deficiencies

Radiographic Examination: In what order do you read a CBCT?

According to Acevedo (2018) 1. Sinuses/Nose: mucosal thickening patterns, calcifications, bubbles, thickening/resorption of sinus wall. 2. Osseous Structures: Low/High density areas, cortical expansion or perforation, well/ill-defined areas, pathology. 3. Soft Tissue: Acne calcification, sialolithiasis, vascular malformations. 4. Dental Structures: Missed canals, calcifications, Resorptions, Widening of the PDL space, fractures, dental anomalies

Radiographic Examination: When viewing a CBCT via MPR, in what order will you view the images?

According to Acevedo (2018): 1. Axial view 2. Coronal view 3. Sagittal view

Diagnosis: A patient is referred to you for pain associated with #3. The apices are closely approximated to the floor of the maxillary right sinus. You cannot see a PARL, and the tooth tests vital. You are highly suspicious that the pain originates with the sinus. What are some tests you can perform clinically to determine the origin of pain?

According to Acevedo (2018): 1. Have the patient lean forward. 2. External finger tap on the anterior wall of the sinus. 3. Have the patient hold their nose and gently try to blow out their nose. A pain response with any/all of these indicates that the pain is originating with the sinus, and is not odontogenic.

Radiographic Examination: What are some reasons for high noise in CBCT images?

According to Acevedo (2018): 1. Low mA → Low photon count →high noise image 2. Open platform 3. Sensor Type (image intensifier creates more noise than a flat panel) 4. Voxel Size: the smaller the voxel, the greater the noise. *Note: the voxel size in and of itself does not determine the resolution of the image. Line pairs/mm is more important. *Ideal image thickness is 1mm*

Radiographic Examination: You have reached the point in reading your CBCT where you're looking at the dental structures. In what order will you look at the teeth?

According to Acevedo (2018): 1. Move from anterior to posterior, and left to right. 2. Look at virgin teeth first. Avoid looking at RCT teeth first. 3. Look at the area of interest. Eval the PDL spaces, cortical bone, pathophysiology, resorptions, etc.

Diagnosis: You notice a large perforation of the hard palate. What would be an immediate differential diagnosis for this?

According to Acevedo (2018): 1. Opioid Abuse 2. Infection (fungal or syphilis) 3. Wegener's Granulomatosis 4. Cancer

Diagnosis: You have a scalloped radiolucent lesion associated with #18-20. Give a differential diagnosis for this radiographic lesion.

According to Acevedo (2018): 1. Traumatic Bone Cyst 2. OKC 3. Central Giant Cell Granuloma

Radiographic Examination: What are the general mA requirements for a Good CBCT image of anterior teeth, bicuspids, and molars. What is a good mA setting for a CBCT image of a tooth that has been previously treated?

According to Acevedo (2018): Anteriors: 6 mA Bicuspids: 7 mA Molars or any ReTx: 8 mA

Radiographic Examination: You are shown a PA of #28-30. You notice a large radiolucent lesion that appears to have resorbed 2-3mm of apical tissue on #29 and the mesial root of #30. Is this lesion benign or malignant?

According to Acevedo (2018): Benign. Benign lesions, because they are slow growing, have the time to resorb roots and expand bone. Malignant lesions move too fast to resorb tooth structure, and they have bony perforations without expansion. - When looking for malignancy: look carefully at the inner cortical outline. If there is a perforation, be highly suspicious for malignancy.

Radiographic Examination: what view type will you utilize for endodontic diagnosis on a CBCT image?

According to Acevedo (2018): MPR: MultiPlanar Reconstruction

Radiographic Examination: What is "Parallax," and why is it important when utilizing a CBCT image?

According to Acevedo (2018): Parallax occurs when the image slice that you are viewing is not parallel with the structure you're observing. In other words, the image is an oblique slice of the object. When an image is in parallax, the measurements will not be accurate. This is particularly a problem when you are trying to avoid major anatomical landmarks (like the IA Canal). *Make sure you adjust your images so they are not in either vertical or horizontal parallax.

Radiographic Examination: How do you describe the densities observed in a CBCT, and how do they differ from the descriptions of a traditional radiograph?

According to Acevedo (2018): The densities in a traditional radiograph are described as radiopaque, radiolucent, or mixed. In CBCT interpretation, they are described as follows: - High density - Low density - Mixed density - Soft tissue density (consistent with areas of known soft tissue - like the brain space or eye space).

Radiographic Examination: T/F: you have a beautiful new CBCT in your office. This makes you a better dentist.

According to Acevedo (2018): False!! Just because you have access to CBCT information, it does not make you proficient in utilizing it.

Treatment: RCT #14. What injection works better, a local infiltration or a PSA?

According to Aggarwal (2011): There's no difference. Go with your preference.

Complications of Treatment: can you give a PDL injection to a hemophiliac patient?

According to Ah Pin (1987): the PDL injection did not produce any hemorrhages of consequence.... Spuller (1988) confirmed that the PDL offers improved reliability of anesthesia without complication.

Prognosis: How successful is the endodontic treatment of obliterated root canals?

According to Akerblom and Hasselgren: In a tooth with no PARL: 98% Success In a tooth with a PARL: 63% Success Overall success rate: 89% Success This justifies NSRCT to treat obliterated canals.

Trauma: What are the common demographics for traumatic dental injuries?

According to Andersson: - Occur most frequently within the first 10yrs of life. - Rarely encountered after the age of 30. - More common in males than females (risk-related behavior)

Treatment: Can you use a composite as a retrograde restorative material?

According to Andreasen (1993): Yes. Cementogenesis may occur over a resin, as long as the resin is not impinging on the PDL space. this can be very difficult to control, given the need to for prime & bond. Additionally, you need exceptional hemostasis. Advantages: immediate setting. Sealing of the dentinal tubules with bond. You can add fluoride to it.

Complications of Treatment: What is the incidence of developing a bacteremia as a result of endodontic manipulation?

According to Bender and Seltzer (1960): If your instruments remained within the canal, there was no bacteremia. If the instruments were extended beyond the apex, there was a bacteremia that lasted for no more than 10 minutes in 1/3 of the cases, regardless of the initial status of the pulp. There are no documented cases of subacute bacterial endocarditis as a result of endodontic treatment.

Complications of Treatment: You have root perforation. Is it better to repair it with gutta percha and sealer, or with amalgam (if those were your only two choices)?

According to Benenati (1986), amalgam had more success than gutta percha. Either way, you don't want to extrude anything beyond the perforation.

Treatment: When performing vertical root extrusion, how often should you be evaluating the patient?

According to Benenati et al (1986), every week, adjusting occlusion as needed

Root Canal Anatomy: How often do mandibular incisors have two canals? How often do they have more than one apical foramen?

According to Benjamin and Dowson (1974): 41% of mandibular incisors had 2 distinct canals. Of those, only 1.3% had distinct separate apical foramina. Lingual canal was the one that was most often missed.

Prognosis: What is the success rate of non-surgical retreatment in cases with a PARL?

According to Bergenholtz (1979): 78% overall success (48% complete resolution, 30% obvious decrease in size of lesion) 22% Failure rate

Pathogenesis: What are the 4 common qualities of a microbial biofilm?

According to Bergenholtz: 1. Metabolic diversity 2. Concentration Gradient 3. Genetic Exchange 4. Quorum Sensing

Treatment: Is the use of ultrasonic irrigation effective at canal debridement?

According to Beus: PUI is as effective at removing bacteria as a final rinse with CHX

Diagnosis/Treatment: what direction does dentinal fluid move when the tooth is exposed to cold/hot?

According to Brannstrom: Cold: fluid moves outward (away from the pulp) Heat: fluid moves inward (toward the pulp)

Anatomy: what is the general pattern of dentinal tubules as you go from enamel to pulp?

According to Branstrom: There are approximately 20K tubules/sq.mm at the DEJ, and 45K tubules at the pulp surface. As you progress towards the pulp, the number of tubules increases

Complications of Treatment/Medical History: You have a senior patient who is taking 81mg ASA daily. You have them planned for root end surgery. Do you take them off their ASA or leave them on?

According to Brennan in 2007: The cardio-protective benefits of ASA outweight the bleeding risks during dental surgery, therefore removing them from the ASA is not indicated unless there are extenuating circumstances (like needing a dry-field for endo). In such cases, discontinuation shouldn't be more than 3 days, and preferably less.

Pathogenesis: The odontogenic keratocyst. Where are you most likely to find it?

According to Brennan: Twice as likely to find it in the mandible compared to the maxilla, and it's usually lurking around the third molar/ramus area. According to Garlock: 9% of OKCs received in the study were located periradicularly, and more than half of those were associated with either necrotic or previously treated teeth.

Radiographic Interpretation: What are the primary reasons for noting a thickened lamina dura on a radiograph?

According to Brynolf, It may reflect one or more of the following: - increased tooth mobility - limited tissue reaction to filling surplus - traumatic occlusion In the past it was considered to be the first sign of periapical disease, however Brynolf showed that this is a poor indicator of disease development. (Ingle's Ch. 16, 6th ed)

Complications of Treatment: You have a failing root canal, and you suspect that the culprit is E. Faecalis. What interim medication will you use for the canal, CHX or CH?

According to Buck, 2% CHX gel is more effective against E. Faecalis than CH.

Treatment: What is your medicament of choice for an interappointment dressing?

According to Bystrom & Sundqvist (1985) Calcium Hydroxide *According to Sjogren & Sundqvist (1991):* -treatment with Ca(OH)₂ for 7 days efficiently eliminated bacteria that survived biomechanical instrumentation. -a 10-min treatment with UltraCal was ineffective. *Law & Messer (2004) strongly support Sjogren & Sundqvist*

Prognosis: Is it worthwhile to retreat a tooth that has been surgically treated already?

According to Caliskan (2005), there is a 61.6% chance of success in non-surgically retreating a case that has been surgically treated already.

Prognosis: What is the success rate for endodontically treating non-perforation internal root resorption lesions?

According to Caliskan and Turkun, success was 100% at a 2-4 year interval. In cases that involved a perforation, success dropped to 25%. This study was completed prior to the introduction of MTA, so the success of perforating resorption cases may increase with its use.

Treatment: You want to remove the smear layer, and elect to use 17% EDTA to do so. How long should you allow the EDTA to sit in the canal to be effective? Can you allow it to sit indefinitely?

According to Calt & Serper: 1-minute soak was enough to remove the smear layer, but a 10-minute soak resulted in excessive dentin erosion.

Complications of Treatment: Will the use of ultrasonics in apical microsurgery cause fractures?

According to Calzonetti (1998): No.

Subjective Examination: What are the two most common complaints with respect to a cracked tooth?

According to Cameron: 1. pain to pressure 2. Thermal sensitivity

Prognosis: what is the most commonly cracked tooth, and where would the crack typically be located on that tooth?

According to Cameron: The mandibular second molar. The crack is typically seen extending from the distal onto the occlusal surface. More common in women, and more common in patients at least 35yo or older.

Application of Biologic Principles: upon setting, what are the products of MTA?

According to Camilleri: calcium silicate hydrate and calcium hydroxide.

Complications of Treatment: Discuss C-shaped canals.

According to Cooke & Cox Summary: Three cases of C-shaped canals in mandibular second molars are described: 2 patients black, 1 patient white. Similar clinical findings in each case included: 1. Difficulty in diagnosing the condition on the preoperative radiograph. (All radiographs gave the appearance of 2 separate roots). 2. All three cases had normal anatomy of the pulp floor and separate canal orifices. 3. All cases had persistent hemorrhage and pain when instruments were used. A review of clinical records of mandibular second molars treated at Univ of Wash 1975-79 found an 8% incidence. They were the first to describe C-shaped canals Simon (1993) states that radiographs can offer some hints to detect C-shaped canals: 1.Roots appear conical as if representing a single root or fused roots. 2.The pulp chamber may appear longer than that of the adjacent molars. 3.The pulp chamber becomes indistinct apically; the pulpal floor usually is not visible 4.Little or no furca is apparent below the pulpal floor. 5.The PDL is indistinct at the apex. Canals cannot be followed in the apical third. The apical foramen is not observable. Treatment: There is usually profuse bleeding as it is difficult to extirpate the pulp in one cut because of multiple foramina. A radiograph of instruments placed in canals often yields an appearance of a furcal perforation with the instruments in the C portion of the canal. It is recommended that full strength bleach and ultrasonics be used when preparing these canals and that thermoplasticized GP be used when obturating. According to Fan: Presented 5 classifications of C-shaped canals, C1-C5. The C-shaped canal was shown to vary in shape considerably at different levels of the canal. The floor of the pulp chamber is usually situated deeply. When present on one side, C-shaped canals have been found on the contralateral tooth 70% of the time. When a C-shaped canal is identified at the orifice, one cannot assume that such a configuration continues throughout the length of the root; use good irrigation and 3D filling techniques

Application of Biologic Principles: How do peripheral acting analgesics work, what are their advantages, and what are their draw-backs?

According to Cooper: MOA: block the cyclo-oxygenase enzyme that converts arachidonic acid to prostaglandins. Advantages: 1. relief equivalent to narcotic combination 2. minimal CNS side effects 3. favorable theraputic index 4. several chemical classes Limitations: 1. plateau effect beyond which more drug provides no additional analgesia (so it doesn't cut it for severe pain) 2. Side Effects (esp. GI irritation)

Application of Biologic Principles: How do Centrally acting analgesics work, what are their advantages, and what are their draw-backs?

According to Cooper: MOA: work at the level of the brain where the endogenous peptides are produced. Mood altering drugs. Advantages: 1. No plateau analgesic effect 2. Analgesic and mood-altering effects Limitations: 1. CNS side effects at therapeutic doses 2. Nausea 3. Drowsiness 4. Urinary retention 5. Constipation 6. Respiratory depression at higher dosages 7. Tolerance and dependence in chronic use.

Medical History: Does Sickle Cell Anemia have an effect on the dental pulp?

According to Costa, yes. Patients with SCA are 8x more likely to develop "spontaneous pulp necrosis" than patients with intact red blood cells. The reason is that SCA can cause ischemia of the pulp due to poor oxygen flow, leading to pulp necrosis.

Complications of Treatment: Your patient has a Type IV sensitivity to latex. Should you be obturating with gutta percha?

According to Costa: avoidance of gutta percha in this situation is not necessary. It is only needed in patients with a documented Type 1 hypersensitivity to natural rubber latex.

Treatment: What are the indications for treatment via root extrusion?

According to Cronin & Wardle (1981) 1. Fracture (transverse or horizontal up to 6mm below the alveolar crest) 2. Internal perforation or external lateral root resorption. 3. Caries (resulting in loss of clinical crown to the alveolar or subalveolar level) 4. Iatrogenic perforation 5. Esthetic gingival contour (to elevate gingival contour lost by traumatic injury or periodontal surgery).

Treatment: With regards to prosthodontic management of vertical root extrusion, How long to you want to keep a vertically extruded tooth in a retainer, and why?

According to Cronin & Wardle (1981), up to 12 weeks, to allow for complete repair of the dentinogingival junction.

Root Canal Anatomy: what is "The Curve of Cunningham?"

According to Cunningham & Senia (Go Air Force)(1992): Mesial roots are not just curved M-D, but B-L as well, and can often be greater in that dimension than in M-D. "The Curve of Cunningham."

Application of Biologic Principles: Describe Metronidazole

According to Cunningham: - bactericidal - causes reduction of a nitro group which results in disruption of DNA synthesis. - effective against anaerobic bacteria - most aerobes are resistant. - suggested that metronidazole be used in conjunction with another antibiotic such as penicillin. - should not be taken with alcohol as an Antabuse-type reaction (flushing, nausea, thirst, palpitations, chest pain, vertigo, hypotension) occurs. - 500mg q6h for 7 days

Application of Biologic Principles: Describe Cephalosporins.

According to Cunningham: - bactericidal, - β-lactams that are less susceptible to β-lactamase activity - no advantage over other antibiotics, recommended only if indicated by susceptibility tests; - 250-500mg q6h 7-10 days

Application of Biologic Principles: Describe Tetracyclines

According to Cunningham: - bacteriostatic - bind to the 30S ribosomal unit and interfere with protein synthesis. - They are used primarily for periodontal infections because they are concentrated in gingival fluids.

Application of Biologic Principles: Describe Clindamycin.

According to Cunningham: - bacteriostatic at low concentrations, bactericidal at high concentrations. - active against most anaerobic bacteria. - binds to the 50S ribosomal unit and inhibits protein synthesis. - actively picked up and transported by PMLs & macrophages into the center of abscesses (a unique property). - associated with development of pseudomembraneous colitis in some individuals (other antibiotics also; overgrowth of C. difficile) causing bloody diarrhea. - Treatment of PC is with oral vancomycin (not absorbed by GI Tract, therefore more available to eliminate Clostridium. - Drug of choice against infections caused by anaerobic bacteria resistant to PCN or in PCN-allergic patients. - 300mg initially, 150-300mg q6h for 7 days.

Application of Biologic Principles: describe Erythromycin.

According to Cunningham: - bacteriostatic agent - binds to the 50S ribosomal unit and inhibits protein synthesis - GI upset is common - NOT the drug of choice for anaerobic dental infections - NOT effective against Prevotella/Porphyromonas spp. - Can be used for PCN-allergic patients with non-serious infections.

Complications of Treatment: what is the major risk of doing an apexification by using long-term CH?

According to Cvek, it is associated with an increased risk for cervical root fracture. Andreason tested sheep teeth, and demonstrated that long-term CH significantly weakened root structures.

Pathogenesis: What is the effect of surgical root end surgery on the flora of a failed root canal?

According to Danin et al (1999), root end surgery alone had no significant effect on the bacterial flora within the necrotic pulp tissue. *Practical Use: Despite an apical plug being created, the massive amounts of entombed bacteria, especially e. faecalis, can possibly find a way out of an unsealed lateral canal, thereby reinfecting the surrounding tissue. Therefore, if possible/feasible, it is best to retreat the tooth first, then proceed to surgery if needed.

Anatomy: What is the difference between a lateral canal, a secondary canal, and an accessory canal?

According to De Deus: Lateral Canal: Extends from the main canal to the PDL in the root body. Secondary Canal: extends from the main canal to the PDL in the apical region. Accessory Canal: Derived from the secondary canal and extends towards the PDL in the apical region.

Root Canal Anatomy: describe basic root canal morphological measurements.

According to Deutch (2004): Measurements were similar for maxillary and mandibular molars. In general, the distance from the cusp tip to pulp chamber ceiling height is approximately 6.0 mm, the distance from the pulpal floor to the furcation is approximately 3.0 mm, and the average height of a pulp chamber is 1.5-2.0 mm. The results of this study agree with those of previous studies (previous was 7mm, 3mm)

Application of Biologic Principles: Tell me about Hydroxyzine.

According to Dionne: 1. It's an antihistamine used for sedation when benzodiazapenes are contraindicated. Limited well-controlled studies on its effect.

Application of Biologic Priniciples: Tell me about Diazepam

According to Dionne: 1. aka Valium 2. Available in 2mg, 5mg, 10mg tablets. Recommend 5-10mg before bedtime the night before the dental procedure. 3. Rapidly absorbed, reaching peak concentration in 60-90 minutes. 4. Half-life is 1.5 days 5. Very safe to use; problems occur when combined with opioids that produce deeper levels of sedation. 6. Has active metabolites the can produce residual sedation after a dental procedure.

Application of Biologic Principles: Is Midazolam a good option for oral sedation?

According to Dionne: It is not approved for oral adminstration (IV is okay). Don't use it orally.

Application of Biologic Principles: T/F: pre-operative Ibuprofen consumption can rduce the severity and onset of post-operative dental pain.

According to Dionne: True.

Prognosis: Prior to the use of MTA as a retrograde restorative material, there were three common dental materials used. What are they, and what were their success rates?

According to Dorn (1990): 1. Super-EBA: 95% Success 2. IRM: 91% Success 3. Amalgam: 75% Success *Note: you may still see IRM used today, based on this study. That's because it's cheap and gets good results* According to Frank & Weine (1992): 58% of cases that were treated with amalgam (and presumed to have healed) were actually healed. This is not good. Amalgam is no longer accepted as a retrograde restorative material.

Complications of Treatment: You have a sulcular perforation, do you use MTA or glass-ionomer to repair it?

According to Dragoo, glass ionomer is recommended over MTA.

Diagnosis: Describe Trigeminal Neuralgia and how to treat it.

According to Drinnan and Baheri (separate studies) Trigeminal neuralgia is pain of neurolgic origin affecting tissues innervated by the trigeminal nerve. Signs/symptoms of TN can include: 1. onset in the 6th-7th decade of life. 2. More frequent in women 3. Restricted to one side at first, and typically it's the right side. 4. Trigger point, paroxysmal pain (sudden bursts) 5. Lancinating, electric-like pain along trigeminal nerve tracts. Treatment: 1. Phenytoin (Dilantin), Tegretol, or carbamazepine. 2. Neurosurgery

Diagnosis: List 6 differential diagnoses for orofacial pain.

According to Drinnan: 1. Trigeminal Neuralgia 2. Maxillary Sinusitis 3. Periodic Migrainous Neuralgia 4. Myocardial Pain 5. Atypical Facial Pain 6. Munchausen's Syndrome

Prognosis: How often do the pulps of mature teeth that undergo extrusive luxation survive?

According to Dumsha: 98% necrose

Etiology: How do endotoxins (Gram negative bacteria) induce inflammation? Can you site a source?

According to Dwyer & Torabinejad, Endotoxin induces cytokines production by host macrophages, which in turn initiates both pulpal and periapical inflammation.

Complications of Treatment: You just perforated a tooth. After muttering inaudibles, you must decide on how to repair the perforation. Is calcium hydroxide a good option for repair?

According to El Deeb (1982): NO! It does not provide an adequate seal, and it leads to extensive bone resorption.

Treatment: What temperature do you set your System B tip to? At what point do you get concerned that you may be inducing thermal injury to the supportive tissue?

According to Eriksson, preventing an increase in root temperature of 10°C will prevent injury to the surrounding tissue. According to Floren: setting your System B tip to less than 250°F will prevent that 10°C increase.

Diagnosis: Describe the 5 classifications of C-shaped canals.

According to Fan: C-Shaped Canal Classification - C1: an uninterrupted C with no separation or division. C-Shaped Canal Classification - C2: the canal shape resembled a semicolon from discontinuation of the C outline. C-Shaped Canal Classification - C3: Two or 3 separate canals C-Shaped Canal Classification - C4: only one round or oval canal in that cross section. C-Shaped Canal Classification - C5: no canal lumen to be observed (usually only seen near the apex).

Pathogenesis: What are the two virulent components of Gram (+) cell walls, and what do they do?

According to Farber and Seltzer (1988): Gram (+) cell walls (Streptococci and Actinomyces) contain Peptidoglycans and Lipteichoic acid. Peptidoglycans: cause granulomatous reactions (acute, followed by chronic, inflammation with spontaneous relapses) LTA: cause cell activation (macrophages) and bone resorption (osteoclastic response to chronic inflammation)

Treatment: What is the advantage of NiTi instrumentation?

According to Glosson & Del Rio: -NiTi stayed more centered and engine driven was faster than hand SS files. According to Baumgartner: -NiTi systems were faster and remained better centered than stainless steel hand files especially at size #40 and up

Etiology: LPS is a virulence factor in endodontic infections. What is it, what does it consist of, and what does it do?

According to Farber and Seltzer (1988): LPS is short for LipPolySaccharide, and is also known as "endotoxin." It is found in the cell walls of Gram (-) bacteria (Prevotella, Porphyromonas, and Fusobacterium. They are heat-stable molecules containing both polysaccharides and phospolipids. LPS exerts its effect by amplifying inflammatory reactions. It is capable of activating the Complement Cascade without antibody (i.e The alternative pathway, which is slower than the classical pathway that does involve antibodies. In the alternative pathway, C3 hydrolyzes into C3a and C3b. C3b binds to LPS, which then initiates the the immune response via Alternative Complement.)

Etiology: Spirochetes are typically found in what type of infection?

According to Farber and Seltzer (1988): Periodontal infections contain anywhere from 30-60% spirochetes, whereas endodontic infections typically contain less than 10%

Application of Biologic Principles: What are the ideal properties of a calcium hydroxide paste, and what are the three vehicles in which it is commonly delivered?

According to Fava (1999): The ideal paste: - mainly calcium hydroxide - non-setting - can be rendered soluble or resorbable - be readily prepared chairside and/or a proprietary paste. Three vehicles used: Aqueous: water soluble. Promotes a high degree of solubility when in contact with tissues. Downside: it can wash out easily and will therefore need to be re-dressed as needed. *UltraCal is an aqueous paste* Viscous: the calcium and hydroxyl ions are released over a longer period of time, and the paste remains in the desired area longer due to its high molecular weight. Oily: lowest solubility, lowest diffusion into the tissues.

Radiographic Interpretation: What are the advantages to taking angled radiographs?

According to Fava: Useful for determining the following: - number, location, shape, size and direction of curvature of roots and canals. - superimposed roots and canals - distinguish between anatomical landmarks and radiolucent apical pathology - position of iatrogenic errors - distinguish between internal and external root resorption - locate foreign bodies following trauma - establish the position of root fractures or resorptive processes.

Anatomy: What lymph nodes may become involved with dental infections?

According to Fehrenbach: - Submandibular Nodes - Submental Nodes - Superior Deep Cervical Nodes - Inferior Deep Cervical Nodes

What is a suitable alternative to calcium hydroxide as an intra-canal medicament?

According to Ferraz, CHX gel, although the ability of CHX to dissolve organic tissues is considered to be poor. The hope is that the gel-form can overcome this deficit by its mechanical action.

Application of Biologic Principles: You have decided to medicate a tooth with calcium hydroxide. How long should you wait until you bring the patient back to complete the root canal, and why?

According to Figdor (1993): Hydroxyl ions derived from calcium hydroxide will diffuse through root dentin and cause pH changes to reach the outer root dentin (thus terminating the osteoclastic activity involved in resorption), but that change takes 2-3 weeks to reach peak levels. Take home message: Let the calcium hydroxide sit for 2-3 weeks if you're going to use it.

Application of Biologic Principles: do antibiotics relieve pain from irreversible pulpitis?

According to Fouad (2002): an antibiotic will not relieve pain from an irreversible pulpitis.

Diagnosis: Describe the ability of patients in general to localize odontogenic pain to one tooth.

According to Friend & Glenwright (1968): Overall accuracy was 37% Maxillary Central Incisor: 63% Maxillary First Premolar: 26% Mandibular Canine: 47% Mandibular Second Premolar: 28% 1.5% of all stimulated teeth were misidentified across the midline, and it occured in the mandible. It is usually possible to narrow it down to within one tooth on either side of the tooth concerned.

Diagnosis: Can a PDL injection be used diagnostically to rule out the source of pain?

According to Fuhs: No. The PDL injection will affect other teeth in addition to the desired tooth, therefore it cannot be used to reliably anesthetize one tooth. Verified by Walton

Application of Biologic Principles: what are the possible causes of parasthesia associated with 4% anesthetics?

According to Garisto: Neurotoxicity is the speculated cause. Lingual nerve was the most affected (likely because is it unfasiculated)

Complications of Treatment: Is it safe to use an apex locator on a patient with a cardiac pacemaker?

According to Garofalo and Kuttler: yes, it is safe.

Complications of Treatment: what precautions do you need to take with regards to the EAL and a patient who has a pacemaker?

According to Garofalo: EAL had no effect on a pacemaker, and the EAL was attached directly to the pacemakers in this study. Wilson confirmed Garofalo's findings in an in vivo experiment. Bottom line: EALs have no effect on pacemakers.

Objective Examination: what is the best medium to use when applying cold refrigerant to a tooth?

According to Garza, a large cotton pellet. It was colder and more predictable than smaller pellets, cotton rolls, or cotton-tipped applicators.

Objective Examination: how many times should you spray a cotton pellet with refrigerant before it becomes too saturated to use?

According to Garza, no more than twice.

Diagnosis: What is a good indication that you may be dealing with referred pain from sinusitis, as opposed to maxillary odontogenic pain?

According to Glick: A group of teeth are typically involved when dealing with a sinusitis, whereas only one tooth is involved with a pulpitis.

Diagnosis: T/F: severity of pain is related to the actual state of the pulp.

According to Glick: False.

Diagnosis: T/F: referred pain can cross the midline.

According to Glick: False. According to Friend and Glenwright, it's possible, but highly unlikely. Remember your experience of an irreversible pulpitis case in #14 that was linked to posterior-orbital pain behind the right eye. Anesthetic administered locally at #14 removed this pain, and its metabolism caused its return.

Diagnosis: T/F: referred pain is always relieved by an interruption of the pain pathway.

According to Glick: True.

Etiology: What are the Indications and rationale for root-end resection?

According to Gutmann & Harrison (1991): Indications: -Removal of pathologic processes -Removal of anatomic variations -Removal of operator errors in nonsurgical treatment such as ledges, blockages, zips, perforations and separated instruments. Rationale: -Removal of the soft tissue lesion is enhanced. -Access to the canal system where the major canal system is blocked for whatever reason as with a post and core is made possible. -Evaluation of the apical seal and/or creation of an apical seal are possible. -Reduction of fenestrated root apices and evaluation for aberrant canals and root fractures can be done.

Complications of Treatment: What is Reactive Hyperemia?

According to Gutmann (1991): Reactive Hyperemia: The rebound phenomenon - At a point in time, the concentration of vasopressor decreases to a level that no longer produces an α-adrenergic effect. Instead of going back to normal, the blood flow increases due to β-adrenergic effects. It is not actually a β effect but a result of localized tissue hypoxia and acidosis caused by the prolonged vasoconstriction.

Subjective & Objective Examination: What are the indications for a surgical endodontic approach to treatment?

According to Gutmann and Harrison: 1. Strong possibility of failure with non-surgical ReTx. 2. If failure with RCT has occured, and ReTx is impossible or would not likely improve the outcome. 3. If a periapical biopsy is necessary

Subjective & Objective Examination: What are the contraindications to endodontic surgery?

According to Gutmann and Harrison: 1. Psychological conditions 2. Systemic conditions 3. Practitioner lack of expertise 4. Unusual bony and/or root configurations 5. Lack of surgical access

Application of Biologic Principles: Is using anesthetic with 1:50,000 epi safe?

According to Gutmann, it is safe with healthy patients or when surgical needs dictate its use. No significant differences were noted in heart rate or arrhythmias during their experimentation.

What changes can be seen in the tooth that has been treated endodontically?

According to Gutmann: 1. 9% moisture loss 2. 5% reduction in tooth stiffness. Larger canal preps/post spaces will compromise the integrity of the tooth. 3. Permanent deformation with loading is more likely, therefore more prone to fracture under applied loads. 4. No significant changes in dentinal toughness. Any changes to dentin (endo or otherwise) may potentially subject it to fracture. 5. Strength of the tooth is directly related to the amount of remaining dentinal thickness.

Medical History: Can anesthetics with vasoconstrictors be safely administered to pregnant/nursing women?

According to Haas, yes.

Complications of Treatment: what is the concern with giving block anesthesia with 4% Articaine?

According to Haas: 4% anesthetics cause problems with paresthesia following block injections. Reader suggests no significant difference between an IA block with Lido and one with Septo.

Application of Biologic Principles: describe the interaction between ASA and anticonvulsants.

According to Haas: ASA may inhibit the main metabolic pathway. Poor evidence of this (case studies only)

Application of Biologic Principles: describe the interaction between APAP and Warfarin

According to Haas: Do not combine the two drugs. Don't combine Warfarin with NSAIDs either.

Application of Biologic Principles: describe the interaction between opioids and alcohol.

According to Haas: Don't combine the two.

Application of biologic principles: What is the maximum dose of epinephrine in a healthy patient? In a cardiac patient?

According to Haas: Healthy: 0.2mg epi (11 cartridges of 2% Lido) Cardiac: 0.04mg epi (2 cartridges of 2% Lido)

Application of Biologic Principles: describe the interaction between ASA and sulfonylureas (oral hypoglycemics)

According to Haas: Increased hypoglycemic effect, avoid this combination.

Application of Biologic Principles: describe the interaction between NSAIDS and Digoxin (antiarryhtmic for congestive heart failure patients)

According to Haas: Increases plasma levels of digoxin

Application of Biologic Principles: describe the interaction between NSAIDS and antihypertensives.

According to Haas: Most anti-hypertensives partially depends on renal prostaglandins, which NSAIDs inhibit. As prostaglandins regulate fluids in the blood (via renin-angiotensin-aldosterone system), their inhibition will lead to an increase in BP (5mm Hg on average). Patients on anti-HTN meds should only be prescribed NSAIDs for 4 days or less. Do not use on elderly patients, or pts with severe congestive heart failure, or have low concentrations of renin. APAP is more appropriate for these patients. Ca channel blockers don't interact with NSAIDs.

Application of Biologic Principles: describe the interaction between NSAIDS and Lithium.

According to Haas: NSAIDs increase the blood concentration levels of lithium, leading to toxicity.

Application of Biologic Principles: describe the interaction between NSAIDS and other NSAIDs

According to Haas: Nephrotoxicity. Do not take NSAID and ASA w/in 48 hours of each other. Do not combine ASA and APAP over a long-term period.

Application of Biologic Principles: describe the interaction between NSAIDS and ethanol

According to Haas: Separate ingestion by 12 hours. Both have side effects on gastric tissues.

Application of Biologic Principles: describe the interaction between APAP and Alcohol.

According to Haas: Severe hepatotoxicity, do not combine in non-alcoholic patients. The combination decreases NAOQI. In alcoholic patients, sudden cessation of alcohol creates a major risks of APAP toxicity. Do not abstain from alcohol if taking this drug.

Application of Biologic Principles: describe the interaction between NSAIDS and Anticoagulants.

According to Haas: The potential exits for excessive bleeding, esp. gastric bleeding. Don't take NSAIDs or ASA

Application of Biologic Principles: describe the interaction between NSAIDS and Cyclosporine

According to Haas: There is a danger for nephrotoxicity (though documentation isn't strong)

Application of Biologic Principles: describe the interaction between ASA and carbonic anhydrase inhibitors (glaucoma patients)

According to Haas: renal clearance is inhibited. Avoid combination.

Application of Biologic Principles: You're getting some hemorrhaging in your surgical site, and you have three materials to choose from that will help you control it: Surgicel, Gel Foam, and Bone Wax. Which one will you reach for?

According to Ibarrola (1985): Gel Foam is the most acceptable hemostatic agent. Surgicel and Bone Wax have a deleterious effect on bone regeneration and if the clinician desires to use these materials, they must be meticulously removed. *Ibarrola in the hole-a. Don't use bone wax in the crypt. Use gel foam.*

Complications of Treatment: You just separated a file. What are the odds that the file is rotary?

According to Iqbal: you're 7x more likely to separate a rotary file than you are a stainless steel file.

Complications of Treatment: The intruded permanent tooth: do you let it re-erupt spontaneously, or do you surgically reposition it?

According to Jacobsen, let it re-erupt spontaneously. Surgical repositioning results in ankylosis and marginal bone loss.

Etiology: what type of bacteria is typically responsible for Subacute Bacterial Endocarditis?

According to Jaspers: 80% of IE is caused by Staphylococcus and Streptococcus bacteria. Alpha-hemolytic or Streptococcus viridans account for anywhere from 22-75% of the cases

Pathogenesis: What is the difference between Acute Bacterial Endocarditis and Subacute Bacterial Endocarditis?

According to Jaspers: ABE: short duration, involving virulent organisms such as Staphylococcus aureus. SBE: longer duration and involves less virulent organisms such as Streptococcus viridans.

Medical History: What are the indicators of Subacute bacterial endocarditis?

According to Jaspers: flu-like symptoms that develop variably and insidiously, which include: headaches musculoskeletal complaints malaise fever chills rigors night sweats Symptoms progress over a period of 2-8 weeks

Complications of Treatment: With which patients is it advised to use local anesthetic without vasoconstrictors?

According to Jastak: -Patients with severe and poorly controlled ischemic heart disease. -Patients with labile cardiac rhythms and potentially life-threatening arrhythmias -Patients with symptoms of uncontrolled hyperthyroidism.

Application of Biologic Principles: what receptors does epinephrine act on, and what are the results?

According to Jastak: Epinephrine is a sympathomimetic that acts on the following receptors: α: Causes peripheral vessel resistance to increase. β₁: Increases heart rate and contractility β₂: decreases peripheral vessel resistance.

Application of Biologic Principles: Is MTA really the best retrograde restorative material out there?

According to Jeannsonne (2003 - go LSU): Geristore may be a superior root-end restorative material with regards to cell attachment and potential biocompatibility. MTA had poor attachment in this in vitro study, so the success of MTA may be related to the attachment of extracellular matrix proteins. According to Gupta (2012): Geristore works well, and was less toxic compared to MTA or glass-ionomer cement. However, it needs to be well-isolated, which is difficult to do in surgery.

Treatment: How effective are the use of CBCT and EAL in determining the WL of a canal?

According to Jeger: Both CBCT and EAL have a high correlation between WLs measured and the actual length of the canal. According to Shabahang: EALs accurately located the apical foramen 96% of the time.

Treatment: are EALs affected by the presence of solutions in the canal space?

According to Jenkins: No.

Objective Examination: What is the advantage of using refrigerant spray over a CO2 stick?

According to Jones (2002): While a CO2 stick is significantly colder than refrigerant spray (tetrafluoroethane), the spray is able to elicit a cold response faster, likely due to the increased volume that a cotton pellet can contain. According to Miller (2004): CO2 can penetrate PFM crowns better when used for 15 seconds or longer, because it is significantly colder than refrigerant.

Treatment: What do you want your ferrule to look like?

According to Juloski: 1.5 - 2mm circumferential ferrule increased fracture resistance

Pathogenesis: Are β-lactam resistant bacteria found primarily in primary infections, or persistent infections?

According to Jungermann: Primary infections.

Etiology: What is the major cause of inflamed pulps and their ability to heal?

According to Kakehashi's landmarks study with germ-free rats in 1965, bacteria is the major determinant of healing in exposed dental pulps.

Etiology: What is the major etiologic force behind the progression of pulpal inflammation to apical periodontitis?

According to Kakehashi, Moller, and Sundqvist: it's bacteria. Kakehashi had a landmark study on germ-free rats. Moller replicated Kakehashi's study with monkeys. Sundqvist confirmed the roll of bacteria in pulpal/periapical inflammation in humans.

Treatment: what is the effect of dipping the master cone in chloroform just before your final seating with sealer?

According to Keane (1984): The chloroform broke down the sealer, leading to apical microleakage and root canal failure.

Pathogenesis: Can you expect a chronic apical periodontitis lesion to lead to anaphylaxis?

According to Kettering and Torabinejad: There is no significant increase in the blood levels of IgE, therefore it is not likely that anaphylaxis will be the result of a chronic periapical lesion. Baumgartner supports this as well.

Treatment: how much of the apex should you remove when doing root-end surgery?

According to Kim (2001) and with an assumed 0° Bevel: -*A 3mm resection* removes 98% of the apical ramifications, and 93% of the lateral canals. - A 2mm resection removes (76%/86%) - A 1mm resection removes (52%/40%) So, you're goal should be to remove 3mm of apex.

Application of Biologic Principles: How does Biodentine compare to MTA?

According to Kim (2015): they are very similar

Treatment: What is the effect of local anesthetics with vasoconstrictors on pulpal blood flow?

According to Kim, it will decrease pulpal blood flow. This is significant because the pulpal blood flow is already minimal, therefore readily creating ischemia. This will lead to toxic build-up, and depending on the duration of ischemia, can lead to irreversible pulpitis.

Biologic Principles: Describe the mechanism of action for corticosteroids.

According to Kragbelle (1989): The corticosteriod passes through the cell wall, binds with a steroid receptor complex to move into the nucleus and bind to DNA. This changes the transcription of the DNA into mRNA, causing both a stimulating effect and an inhibitory effect. - stimulates the production of lipocortin, which then inhibits the activity of phospholipase A2. Phopholipase A2. Phospholipase A2 releases arachidonic acid, which is the precursor of prostanoids and leukotrienes, which are integral in the inflammatory process. By limiting Phospholipase A2, corticosteroids limit inflammation. - inhibits mRNA responsible for IL-1 formation. IL-1 is integral in the immune response. Therefore, corticosteroids, by inhibiting IL-1, is suppressing the Immune System.

Treatment: How should your access shapes look?

According to Krasner and Rankow, they should reflect the anatomy of the pulp chamber.

Complications of Treatment: A patient is referred to your endodontic office for an evaluation and treatment of #19. The referring dentist gives a provisional diagnosis of Symptomatic Irreversible pulpitis/Normal Apical Tissues. Your radiographs show a mesial radiolucency consistent with caries, which extends half the distance from the radiographic DEJ and the pulp chamber. The tooth has an existing occlusal amalgam, approximately 3mm in depth, and with at least 2mm of dentin between the pulpal margin and the nearest pulp horn. Patient is a 4/10 pain scale, with constant pain, but especially with exertion. Upon asking what the pain feels like, the patient says it feels like a lot of pressure and a burning sensation. At this point, what should be your main concern?

According to Kreiner: Cardiac pain is often described as pressure and burning, and the classic orofacial manifestation is mandibular left pain, particularly upon exertion. It is not relieved with local anesthesia, but can be relieved with nitroglycerin if a myocardial infarct is in its early stages.

Prognosis: You have a tooth with a marginal ridge fracture and reversible pulpitis. What are the odds that this tooth will need a root canal in 6 months?

According to Krell (2007): 20% chance. If the pulp has not succumbed within 6 months, a root canal will likely not be necessary in the future.

Complications of Treatment: What percentage of people with a cracked tooth will develop an irreversible pulpitis or necrosis following crown placement?

According to Krell: 21%

Etiology: Is there a difference in pulpal pathology with teeth restored with either resin, amalgam, or crown?

According to Kwang: Resin is 1.9x more likely to require endodontic treatment than amalgam. Resin is 5.6x more likely to require endodontic treatment than a crowned tooth. Dawson contradicts Kwang: Crowned teeth had more apical periodontitis, and he found no difference in pathology when comparing resin and amalgam. *Clinical relevance: it's widely known that placing a well-sealed resin is more difficult than placing a well-sealed amalgam. The results from these two authors would suggest that the quality of the restorations they were looking at were likely different, therefore different outcomes.*

Radiographic Interpretation: What size would a PARL have to be in order to predictably consider it a cyst?

According to Lalonde (1970): 16mm in diameter in any direction

Radiographic interpretation: What percentage of PARLs are cysts?

According to Lalonde (1970): 44%

Diagnosis: At what radiographic size would you strongly suspect a PARL to be cystic?

According to Lalonde: 200mm² or larger (i.e the lesion is 16+mm in diameter in any direction)

Radiographic Examination: What are the steps for accurately describing an image?

According to Langley and Acevedo: 1. The number (1, 2, or multiple) 2. The Size (Small, Large, or specific dimensions) 3. Shape (round, ovoid, triangular, or irregular) 4. Periphery: Poorly defined (acute) or well-defined (chronic). If well-defined, is it corticated or non-corticated. 5. Density: radiopaque/lucent; High/low/mixed/soft-tissue density 6. Location 7. Effect on surrounding structures. Resorption, displacement, expansile, perforated. 8. Differential Diagnosis

Anatomy: How common are alveolar fenestrations and dehiscences?

According to Larato (1970) - large sample size: 7.5% of all teeth demonstrated either a dehiscence or a fenestration

Treatment: You have finished Phase 1 of Regeneration and have placed CH. How long do you wait before completing Phase II?

According to Law: 2-4 weeks.

Treatment: Using ferric sulfate for hemostasis during surgery. Good idea or bad idea?

According to Lemon & Jeansonne (1993): As long as you clean it all out, then it had no long-term effects. That said, ferric sulfate was found to be an irritant and will delay healing if left in situ.

Trauma: a tooth has been traumatized, but definitive treatment cannot be ascertained yet. How often should you conduct vitality testing?

According to Levin, the gold standard is: - Immediately post-trauma - 2 weeks post-trauma - 4 weeks - 6-8 weeks - 6 months - 1 year

Treatment: Discuss the treatment protocol for the various types of Dens Evaginatus. Type I DE and treatment plan

According to Levitan & Himel (2006): Type 1 DE: Normal pulp, mature apex— Reduce opposing occluding tooth, apply flowable to tubercle. Evaluate every 6-12mo. When reevaluation demonstrates adequate pulp recession, remove tubercle and apply resin. Type II DE: Normal pulp, immature apex— Same as Type I except reevaluation every 3-4 months until development of a mature apex and pulpal recession. Type III DE: Inflamed pulp, mature apex - RCT Type IV DE: Inflamed pulp, immature apex—Shallow MTA pulpotomy followed by restoration. Type V DE: Necrotic pulp, mature apex: RCT Type VI DE: Necrotic pulp, immature apex—MTA apexification and restoration (or possible regeneration case now).

Treatment: You have a tooth with true "sterile necrosis." Do you treat it?

According to Lin et al (2006): NSRCT is advocated for the following reasons: 1. devitalized pulp tissue is completely devoid of innate and adaptive immune defense mechanisms 2. devitalized pulp tissue can easily get colonized and become infected with just the smallest number of bacteria gaining access to it. 3. Prevention of disease. The prognosis of RCT of teeth with PARL is lower than that of teeth with no PARL. (ie an ounce of prevention is worth a pound of cure).

Complications of Treatment/Medical History: What is the best therapy for a bleeding problem?

According to Staffileno: Prevention. A careful medical history may prove more useful than any lab tests.

Treatment: Describe the Papilla-based Incision.

According to Lubow (1984): The horizontal component of this flap is directed at and along a straight line drawn across the most apical extent of the facial gingival scallop. In other words, the incision would be initiated in the gingival sulcus at the cervical region of each tooth; however, as the sulcus curves coronally in the interproximal area, the incision proceeds in a straight line to connect with the cervical area of the adjacent tooth. -First to describe papillary sparring flap design with straight horizontal line Advantages: rapid, predictable, recession-free healing. (Velvart)

Complications of Treatment: You just separated a file. What are your options?

According to Madarati: 1. Orthograde removal 2. Retrograde removal or entombment of the fragment. 3. Bypass 4. Leave in place and monitor.

Complications of Treatment: You have started a root canal, but have not gotten too far when your spouse calls and says one of your children fell off the trampoline and was knocked unconscious and has broken a leg. An ambulance is taking your child to the hospital, but you're not sure whether or not the child will survive. You obviously need to leave as soon as possible. How do you manage your patient, who is in the chair with an open tooth and in the middle of treatment?

According to Maddox & Walton (1977): A dry cotton pellet performed as well as any other intracanal medicament with regards to the incidence of post-operative pain. Note: this doesn't mean it will control the bacterial count in the canal system (which will rise), but it will control the post-operative pain.

Complications of Treatment: what are the signs of an oncoming syncope?

According to Malamed: - Pale - Sweaty - Nauseous - Dizzy

Complications of Treatment: How do you manage a syncope patient, and at what point do you contact EMS?

According to Malamed: - Trendelenberg positioning (supine, feet elevated), monitor airway, breathing, and circulation. Cold compress on the forehead to reduce vascular size and retain blood in the head. - Patient should regain consciousness within 10 seconds. If not, contact EMS. Contacting EMS is rare. - Don't let the patient drive home alone or leave unescorted.

Treatment: How much anesthetic should you deposit when doing a PDL injection?

According to Malamed: 0.2ml has been proven to be effective.

Complications of Treatment: What are the six most common medical emergencies in the dental office?

According to Malamed: 1. Unconsciousness (Syncope) 2. Altered Consciousness (Hypoglycemia) 3. Convulsions (Seizures) 4. Respiratory Distress (Asthmatics/Anxiety) 5. Drug-related Crises (Overdoses/Allergic Rxn) 6. Chest pain (Angina/Myocardial Infarction)

Treatment: How effective is the Gow-Gates injection?

According to Malamed: 97% of injections provided adequate pain control.

Complications of Treatment: A patient begins acting strangely (altered consciousness). What is the most common cause of this, and what can you do about it?

According to Malamed: Altered consciousness (aggravated, "not with it") is most often caused by hypoglycemia. Signs of Hypoglycemia: - Confusion - cool moist skin - mild tremor - headache - hunger Treatment: - if conscious: make them comfortable. Monitor vitals, give them sugar. Only call EMS if sugar doesn't resolve the problem. - if unconscious: place them supine and begin BLS.

Application of Biologic Principles: What is the primary difference between articaine and lidocaine?

According to Malamed: Articaine has an aromatic ring in its structure, and it's degree of protein binding is 95% stronger than most other anesthetics. This allows for a more efficacious duration of anesthetic.

Complications of Treatment: a patient convulses in your chair. What do you do?

According to Malamed: Do not place anything in their mouth, ensure they're in a safe area (pull back dental carts/instruments, etc), allow the convulsion to take its course. If it continues for more than 5 minutes, IV anticonvulsants are needed, therefore call EMS.

Complications of Treatment: A patient in your chair, with a history of asthma, develops an acute respiratory reaction. What do you do?

According to Malamed: Ideally have their own bronchodilator available and ready for use. Seat them up in a comfortable position after removing everything from their mouth. Administer a bronchodilator. Call EMS if the patient is not responding after two doses from the bronchodilator.

Complications of Treatment: a patient complains of chest pain while in your chair. What do you do?

According to Malamed: If angina is suspected, administer nitroglycerin. If no history of past chest pain, call EMS. After two unsuccessful doses of nitroglycerin, assume it's an MI. If MI is suspected, call EMS, begin MONA protocol: Morphine: 2-5mg q5-15min Oxygen Nitrous Oxide (35-65%) Aspirin: full-strength If patient becomes unconscious: begin BLS.

Complications of Treatment: what is the most common medical emergency in the dental office?

According to Malamed: syncope.

Application of Biologic Principles: Roths's sealer and CH, good mix or bad mix?

According to Margelos, residual CH in the canal space inhibits the set of eugenol-based sealers.

Application of Biologic Principles: is sealer really necessary, or can we just obturate with gutta percha?

According to Marshall & Massler: Sealer is essential for effective root canal obturation. Gutta percha = chip Sealer = dip

Prognosis: Does pre-treatment pain correlate with post-treatment pain?

According to Marshall and Walton (1984), yes, there is a definitive correlation.

Treatment: Why isn't full-strength NaOCl used for regeneration cases?

According to Martin: it reduces stem cell viability and differentiation. A lower concentration of 1.5% is recommended, as well as 17% EDTA. This mixture improved cell viability.

Radiographic Examination: is "enhancing" your digital images a good thing? Why/Why not?

According to McClanahan et al (2006), images with enhanced contrast produced significantly more accuracy than an unenhanced image. So filter your images.

Radiographic Examination: What root is most frequently associated with odontogenic sinusitis?

According to McClanahan et al (2011), it's the palatal root of the maxillary first molar, followed by the MB root of the Maxillary Second Molar.

Biologic Principles: What are the 6 biological factors that lead to asymptomatic radiolucencies persisting after root canal treatment?

According to Nair (2006) 1. intra-radicular infection persisting in the complex apical root canal system. 2. extra-radicular infection, generally in the form of periapical actinomycocis. 3. extruded root canal filling or other exogenous materials that cause a foreign body reaction. 4. accumulation of endogenous cholesterol crystals that irritate periapical tissues 5. true cystic lesions 6. scar tissue healing of the lesion. In Short: 1. bacteria inside the tooth 2. bacteria outside the tooth 3. foreign object 4. cholesterol crystals 5. Cyst 6. Scar tissue

Treatment: Why can't you achieve adequate regional anesthesia in the presence of infection?

According to Najjar: The degree of anesthesia depends primarily on the concentration of the solution permeating the nerve fiber. -degenerative changes during inflammation can contribute -proteolytic enzymes produced during inflammation can lead to the breakdown of the anesthetic. Inflammatory and infectious environments have lower pH levels than normal. It takes anesthetic with a lower pKa value to allow its un-ionized base to pass through the neuronic membrane and achieve nerve blockade.

Etiology: What are the 6 pathways to pulpal infection?

According to Narayanan (2010) 1. Dentinal Tubules 2. Open Cavity 3. Periodontal Membrane (Ligament); prophylaxis tx; luxation injury, epithelial invagination into a periodontal pocket (think lateral canals on all of this) 4. Blood Stream (anachoresis) 5. Faulty Restoration 6. Extent (infection from an adjacent infected tooth via the continuous flow of tissue).

Treatment: How long do you apply a splint for in most trauma cases that require one?

According to Nasjleti and confirmed by Kehoe, a splinting period of 7-10 days is recommended. Cvek and Andreasen also recommend 7-10 days, though it may not be needed if the mobility is minimal. They also recommended a longer splint time if alveolar fracture is involved.

Application of Biologic Principles: You have decided to place calcium hydroxide in a tooth with external resorption. How long do you apply the calcium hydroxide?

According to Nerwich: the pH of the outer root dentin will increase after 2-3 weeks of calcium hydroxide. Therefore, 2 weeks is advocated.

Treatment: What is the effect of cotton on the seal of a provisional restoration?

According to Newcomb, even the smallest amount of cotton trapped in the temporary material reduced its sealing quality.

Complications of Treatment: you determine that the source of your patient's pain is non-odontogenic. What are the other possible sources of pain?

According to Nixdorf: 1. musculoskeletal pain 2. Neuropathic pain 3. headaches 4. Pathology related to nearby structures, including: Maxillary sinuses, salivary glands, vasculature, brain tumors, angina, or throat cancer.

Application of Biologic Principles: Is there any advantage of premedicating a patient with pre-operative pain with ibuprofen?

According to Noguera-Gonzalez: IBU was 72% successful at allowing anesthesia, vs. 36% success with the placebo.

Treatment: What teeth are contraindicated for internal ("Walking") bleach?

According to Nutting and Poe: Teeth with fractures, cracks, hypoplastic enamel, and severely undermined enamel. *Walking Bleach was introduced by Spasser, term was coined by Nutting and Poe.*

Treatment: What are the indications and contraindications for root resection and hemisection procedures.

According to O'Leary (1981): Root resection and hemisection procedures. 1981 Indications for root resection and hemisection: 1. Furcal invasions by inflammatory periodontal disease that are not amenable to root planning, surgical flap, and oral hygiene procedures. 2. A non-restorable carious lesion involving one root of a multirooted tooth. 3. Fracture of a single root of a multirooted tooth. 4. Perforation of a root during endo therapy. 5. Partial calcification of a root canal not amenable to conventional or retrograde endo. 6. Severe dilacerations of a root or broken instrument. Contraindications: 1. Extensive bone loss, furcation involvement, and/or mobility 2. Fused roots 3. Root(s) to be retained are short or thin 4. Ineffective oral hygiene 5. High caries risk 6. Inoperable canal(s) in roots to be retained 7. Systemic contraindications 8. Limited surgical access (ex. DB root of max 2nd molar)

Diagnosis: Discuss Dens Invaginatus and their associated crown formations.

According to Oehlers (1957): Dens Invaginatus Type I: Invagination is enamel lined, confined within the crown, and doesn't extend beyond the CEJ. Dens Invaginatus Type II: The enamel-lined invagination invades into the root but remains confined within it as a blind sac. There may, however, be a communication with the pulp Dens Invaginatus Type III: The invagination penetrates through the root and "bursts" apically or laterally at a foramen. There is usually no communication with the pulp. The invagination may appear to be completely lined by enamel, but more often a portion of it is lined by cementum instead. Dens Invaginatus Anterior Crown Group I: Normal in appearance except for an abnormally deep lingual pit accompanied by a slight over development of the cervicolingual ridge. (usually Type I invanginations). Clinically it is impossible to detect this invagination and it is recommended that all incisor teeth with deep lingual pits be radiographed and evaluated. Dens Invaginatus Anterior Crown Group II: The crown is conical, peg, or barrel shaped with an incisal pit, which may lead to an invagination. This type I invagination appears to be a result of enclavement of a portion of the enamel organ during the process of lingual rotation and fusion. A variant of the barrel-shaped incisor is seen where there is a central ridge on the reduced lingual fossa so it resembles a mandibular first premolar. There may be 2 lingual pits, one on each side of the ridge. An invagination may arise from either one or both. Dens Invaginatus Anterior Crown Group III: The labial appearance of the crown is normal but occasionally be caniniform. Lingually there is an exaggerated cingulum often referred to as a "talon cusp" or lingual "tubercle". There is often a pit on either side of the cingulum deep to the lateral ridges and a Type I invagination may arise from one or both of these pits. All three of these crown forms described a type I invagination, but obviously an invagination could extend more apically in any of the three forms to form a type I, II or III invagination. Posterior Crown Anomaly Group 1 - Dens Invaginatus: the crown has a normal or near normal appearance, but the occlusal surface may show a complicated fissure pattern and invaginations may arise from an occlusal fissure or pit. Posterior Crown Anomaly Group II - Dens Invaginatus: most common posterior crown form, analogous to the barrel-shaped or conical crown forms of anterior teeth. The crown is diminutive and dome shaped with a deep central depression on its convex occlusal surface. Fissures radiate irregularly over the surface from the occlusal depression giving the appearance of infolding of the cusps towards the invagination. The central depression leads to the invagination. Posterior Crown Anomaly Group III - Dens Invaginatus: the crown portion of the odontome is larger than normal and there is a distinct supernumerary element. The occlusal surface may show a general irregular cuspal/ fissure pattern. The invagination arises from an occlusal fissure between the supernumerary element and the crown proper. The theories on the mode of formation on invaginated teeth according to Oehlers are discussed. These involve an in-folding of the epithelium with abnormal proliferation.

Diagnosis: Discuss Dens Evaginatus. Oehlers, Lee, Lee. 1967. Dens evaginatus (Evaginated odontome) - Its structure and responses to external stimuli.

According to Oehlers (1967): Dens evaginatus has a hallmark thin, enamel-covered tubercle projecting from the occlusal surface of - mainly - premolars. Through fracture or wear, the underlying pulp usually becomes infected. Treatment: Occlusal adjustment alone is not sufficient. An aseptic direct pulp cap in immature teeth is appropriate, or a root canal in a fully-mature tooth. Prevalence (according to Yip in 1974): 4% incidence in the Chinese population 84% mandibular premolars 16% maxillary premolars When present, 90% were bilateral and symmetrical

Anatomy: What are the dimensions of the mental foramen? Where is the mental foramen relative to the mandibular premolars? Relative to the Inferior Border of the Mandible?

According to Phillips & Weller (1990-1992): Dimensions: - Horizontal: 4.6mm - Vertical: 3.4mm *Note: left mental foramen typically larger than the right* Direction of Canal Exit: - Posterior/Superior: 69% - Superior: 22% Location Relative to the Premolars: - Inf. to the crown of the 2nd Premolar: 63% - Mes. to the crn of the PM2: 18% (ave dist=1.9mm) - Dis. to the crn of the PM2: 19% (ave. 2.2mm) Location Relative to the Mandible: Ave dist. from buccal cusp of PM2 = 36mm Ave dist from buccal cusp of PM2 to foramen = 21.8mm *Mental foramen is typically found at a ratio of 60% of the distance from the buccal cusp tip of PM2 to the inferior border of the mandible.

Anatomy: Where is the mental foramen relative to the apex of the mandibular 2nd premolar?

According to Phillips & Weller (1992): Mesial to the apex of PM2 (3.8mm): 71% Inferior to the apex of PM2 (3.5mm): 75%

Anatomy: How do the radiographic measurements of the mental foramen compare with the actual measurements?

According to Phillips & Weller (1992): The radiographic size is typically smaller than the actual size. The radiographic size corresponds to the smallest diameter of the foramen on the internal surface of the buccal plate. A panoramic radiograph will shift the foramen distally, and magnify everything in the mandible by 23%.

Radiographic Interpretation: what is the most common direction of exit of the mental canal?

According to Phillips and Weller: posterior-superior direction 69% of the time

Application of Biologic Principles: You have a mechanical pulp exposure and decide to do a direct pulp cap with calcium hydroxide in anticipation of a dentinal bridge formation. Where does the calcium in the dentin bridge come from?

According to Pisanti (1964), it likely comes from the pulp. It does NOT come from the calcium hydroxide itself.

Treatment: What is the dentin penetrating efficacy of CHX and NaOCl?

According to Pitt Ford (1993): 100µm

Complications of Treatment: Calcium hydroxide was extruded beyond the apex and into the mandibular canal space. How fast does that canal need to be treated?

According to Pogrel: Microsurgical treatment of the canal needs to take place within 48 hours of the incident for maximal success.

Pathogenesis: What immunoglobulins can you expect to find in a periapical granuloma?

According to Pulver: IgG = 70% (primary defense against bacteria/viruses) IgA = 14% (associated with mucous membranes) IgE = 10% (Activates the response to allergens - can lead to anaphylaxis) IgM = 4% (1st immunoglobulin to fight infection. Found in Blood and Lymph)

Diagnosis: How often are teeth responsible for maxillary sinus infections?

According to Radman (1983): 10% of sinusitis cases.

Complications of Treatment: you decide to retroprep a tooth with ultrasonics over a bur. Wouldn't that increase the amount of microfractures to the tooth?

According to Rainwater, Ultrasonics are no more likely to crack root structure than burs.

Prognosis: Describe the relationship between endodontic treatment and restorative treatment on the success of the overall treatment.

According to Ray & Trope (1995): *The crown is more important than the endo*. This sentiment is shared with Siquiera (2005) Good Crown +/- Good Endo: 80% success Good Endo +/- Good Crown: 76% success Poor Crown +/- Good Endo: 51% success *Poor Endo +/- Good Crown: 70% success* Good Endo+ Good Crown = 91% success Good Endo + Poor Crown = 44% success Poor Endo + Good Crown = XX% success Poor Endo + Poor Crown = 18% success *all results are based on radiographs* According to Ricucci (2000): *The Endo is more important than the crown* Good Crown +/- Good Endo: 80% success Good Endo +/- Good Crown: 76% success Poor Crown +/- Good Crown: 49% success *Poor Endo +/- Good Crown: 30% success* Good Endo + Good Crown = 91% success Good Endo + Poor Crown = 44% success Poor Endo + Good Crown = 68% success Poor Endo + Poor Crown = 18% success

Prognosis: Good Endo/Bad Restorative vs. Bad Endo/Good Restorative with regards to periodical inflammation. Go.

According to Ray & Trope: Good Endo/Bad Restorative = 44% Success Bad Endo/Good Restorative = 68% Success Ricucci disagrees with this.

Prognosis: What are the success rates for good endo with poor coronal restoration, and poor endo with a good restoration.

According to Ray and Trope (1995) Good Endo/Poor Crown: 44% success Bad Endo/Good Crown: 68% success *Conflicts with Ricucci*

Objective Examination: what factors may affect the accuracy of your diagnosis?

According to Read: Taking Ibuprofen before the exam could significantly affect the results of percussion, palpation, and cold testing. According to Fowler: The combination of APAP and hydrocodone had no effect on cold testing in patients with symptomatic irreversible pulpitis.

Application of Biologic Principles: what anesthetic is better in the PDL injection, Articaine or Lidocaine?

According to Reader et al, there was no difference in the use of 4% Articaine vs. 2% Lidocaine. Their efficacies were similar.

Complications of Treatment: do you have any cardiovascular concerns with regards to an IO injection?

According to Reader: An IO injection is a vascular injection, therefore when injecting an anesthetic that contains epinephrine, you can expect an increased heart rate. Reader indicates that a healthy patient will experience a transient increase in heart rate that will subside within 4 minutes. In patients with cardiovascular concerns, the use of 3% Mepivicaine Plain is a suitable alternative. There is no advantage to using Articaine over Lidocaine.

Application of Biologic Principles: Between Lidocaine and Marcaine, which anesthetic is more effective with maxillary infiltrations?

According to Reader: There's no difference.

Treatment: You just created a pulpal access cavity and completed a root canal on #19. How much compressive strength did the tooth just lose? How does that compare to an occlusal cavity prep, and an MOD cavity prep?

According to Reeh & Messer, a 5% reduction in compressive strength. Occlusal prep: 20% reduction MOD prep: 63% reduction

Application of Biologic Principles: Are there any advantages to using inhaled nitrous oxide for analgesia?

According to Stanley: There is a significant difference. There is a documented analgesic effect with higher concentrations of nitrous (30-50%)

Pathogenesis: You have a failing root canal with a clear PARL and a sinus tract. Would you expect to find any significant purulence in this infection? Why/Why not? What is the liklihood that this case is asymptomatic?

According to Reynaud & Haapasalo (2005), E. Faecalis induced little/no release of hydrolytic enzymes from the PMN cells. With this inhibition of PMN (neutrophil) activity, it is unlikely that you will find any significant purulence. For this same reason, the case is likely to be asymptomatic. Stuart (2006) also confirms the likelihood of the cases trending towards being asymptomatic

Pathogenesis: How often is a periapical lesion associated with a biofilm?

According to Ricucci (2003): 4% of roots w/lesions had a biofilm.

Treatment: Describe the Balanced Forces Technique.

According to Roane (1985): This technique is designed for curved canals. -Placement is accomplished using a clockwise rotation of no more than 180 degrees with slight inward pressure. -Cutting is accomplished with a counterclockwise motion and inward pressure matching the files strength. -Cleaning or debris removal is done using 1-2 non-cutting no pressure or slight outward pull clockwise motions. (Normally, cleaning is done only after the desired length has been reached and maintained with a counterclockwise rotation. However, on occasion the file becomes clogged with debris and will hesitate to accept the next placement motion. Then the file must be removed, cleaned, and then re-inserted.) -Clockwise rotations should be limited to no more than 180 degrees to prevent over-insertion of the apical portion of the instrument. -Counterclockwise cutting motions use a rotation of 120 degrees or more.

Radiographic Examination: What is the value of a BWX radiograph in endodontic treatment?

According to Robinson et al: 1. Provides and accurate representation of the location and size of the pulp chamber 2. Can aid in the design of the endodontic access preparation.

Pathogenesis: Would you be more likely to find E. Faecalis in apical diagnoses that are symptomatic, or in periapical diagnoses that are asymptomatic?

According to Rocas and Siqueira (2004): e. Faecalis is more likely to be found in asymptomatic cases. Additionally, it is 9x more likely that E. Faecalis will be found in ReTx cases, than in NSRCT cases.

Complications of Treatment: Is there any benefit in reducing occlusion for the purpose of preventing a post-operative flare-up?

According to Rosenberg: occlusal reduction should prevent post-operative pain in those patients whose teeth initially exhibit pulp vitality, percussion sensitivity, pre-operative pain, and/or absence of a periradicular radiolucency.

Diagnosis: Is CBCT effective at differentiating cysts and granulomas?

According to Rosenburg, no.

Treatment: what is the main advantage of using CHX over calcium hydroxide?

According to Rosenthal: Excellent substantivity. It has been shown to be effective for up to 12 weeks, and is effective with E. Faecalis.

Application of biologic principles: you are doing a regeneration case. What interim medicament will you use for the canal space, CHX , Abx paste, or CH?

According to Ruparel: CH is less cytotoxic to the apical stem cells than Abx paste or CHX.

Diagnosis: You find some unusual anatomy with regards to your exam on #14. How likely are you to find the same unusual anatomy on #3?

According to Sabala (1994): unusual anatomy can be found bilaterally 60% of the time. The more unusual the anatomy, the more likely it is to be found bilaterally.

Etiology: what is the most common virus found in necrotic teeth?

According to Sabeti (2004) herpesvirus

Application of Biologic Principles: How does calcium hydroxide affect bacterial LPS (endotoxin)?

According to Safavi (1994): Calcium hydroxide destroys the ester-links of hydroxy fatty acids that LPS requires, thus detoxifying residual LPS and limiting bone resorption.

Complications of Treatment: How often does post-operative pain occur following endodontic treatment?

According to Sathorn: Anywhere from 3%-58% According to Mattscheck: the degree of post-op discomfort is significantly influenced by the pretreatment pain level.

Complications of Treatment: How and why to rotary NiTi files fail?

According to Sattapan (2000): Rotary NiTi files failed more in torsion (56%) than from cyclic fatigue (44%). Usually from too much apical force.

Application of Biologic Principles: What is the mechanism of action for calcium hydroxide against Gram (-) bacteria?

According to Savafi: Calcium hydroxide hydrolyzes the lipid moiety of LPS (endotoxin), thus degrading the cell wall.

Radiographic Examination: What are the 4 keys to becoming proficient with the use of CBCT?

According to Scarfe (2012): 1. Acquisition 2. Data Correction 3. Data Navigation 4. Data Interpretation

Application of Biologic Principles: Endodontically treated teeth have a 9% moisture loss. Some have suggested a reduction in toughness and strength as a result. Do you agree?

According to Schilder: Dehydration will increase the stiffness and decrease flexibility; it does not weaken the dentin structure with regards to strength and toughness. Sedgley reinforces the idea that endodontically teeth are weaker because of a loss of tooth structure, NOT because of dehydration.

Treatment: What are the benefits of using transillumination during apical surgery?

According to Schindler (1994): 1. detection of vertical root fractures 2. location of calcified, undebrided canals 3. evaluation of complete circumferential resection of the root end 4. detection of unusual apical anatomy 5. detection of extra canals 6. location of fins and isthmuses between canals 7. evaluating the quality of debridement and obturation of the root canal.

Treatment: List 7 key points in restoring endodontically treated teeth.

According to Schwartz and Robbins: 1. Avoid bacterial contamination 2. Protect the posterior teeth with full cuspal coverage restorations. 3. Preserve Tooth Structure 4. Use posts with adequate length to retain the core 5. Enhance resistance of posts via ferrule and antirotational design. 6. Use posts that are retrievable. 7. Make sure your provisional is well-placed.

Prognosis: What is the difference in success rates between flush fills, underfills, and overfills? What is the difference in success rates between teeth with lesions and and teeth without?

According to Seltzer and Bender (1963): Over Fill: 71% Flush Fill: 87% Under Fill: 87% Lesion: 76% No Lesion: 92% According to Sjogren and Sundqvist (1990) - confirmed by Walton in 2005: Over Fill: 76% W/in 2mm of the apex: 94% >2mm short: 68% Lesion: 86% No Lesion: 96% ReTx w/ apical periodontitis: 62%

Complications of Treatment: What type of bacteria are typically associated with flare-up pain?

According to Seltzer: Gram (-) anaerobic bacteria: mainly due to their enzymatic products and endotoxins that they produce

Etiology: What factors are associated with pulp calcifications?

According to Sener: Deep caries/restorative treatment Excessive forces due to occlusion or trauma Systemic medications (corticosteroids, statins) Systemic Disease

Treatment: How effective are apex locators?

According to Shabahang: 96% effective According to Baumgartner: 91% effective

Treatment: What is the effect of using full-strength NaOCl as a canal irrigant? Is it toxic?

According to Shih & Rosen (1970): -5.25% NaOCl gave immediate sterilizing effects, but could not completely sterilize the canal system. According to Senia (1971): -NaOCl is more effective than saline at removing pulp tissue from instrumented canals. According to *Spangberg* (1973): -full-strength is too cytotoxic. According to *Harrison, Hand, Baumgartner* (1978): using full-strength NaOCl did not increase the incidence/degree of interappointment pain. Further, diluted NaOCl significantly decreases the ability to remove necrotic tissues. According to Rosenfeld (1978): -NaOCl only has a surface effect for vital pulp tissue.

Anatomy: What percentage of teeth have a cervical gap between enamel and cementum?

According to Shiloah:10%

Complications of Treatment: What are the causes of perforations, how do you correct it, and what is the prognosis dependent upon?

According to Sinai (1977): *Causes* - Resorption - Caries - Operator Error *How to Correct* 1) Perforation sealed during routine endodontic treatment (seal during obturation with softened gutta-percha and sealer). 2) Perforations sealed as an additional canal. 3) Perforations sealed with amalgam via the chamber (must avoid extrusion of material - internal matrix to contain amalgam). 4) Perforations sealed with amalgam using a surgical approach. 5) Perforation repaired by stimulation of calcification using calcium hydroxide. 6) Root-end resection, root amputation, or hemisection. *Prognosis* Dependent upon the following: - Location - Time - Possibility of Sealing - Accessibility of the Main Canal

Complications of Treatment: You just perforated a tooth. What are the prognostic factors that will affect the outcome of this situation?

According to Sinai and El-Deeb: 1. Perforation Size 2. Perforation Location 3. Time it took to repair it. 4. Provider Experience 5. Post placement following repair 6. Ability of the clinician to seal the defect 7. Prior microbial contamination

Complications of Treatment: Your endo treated tooth has an open margin. How long can the gutta percha be exposed coronally before ReTx is indicated?

According to Siqueira (2001): 30 days.

Pathogenesis: What are the mechanisms for fungal pathogenicity?

According to Siqueira (2004): 1. Adaptability to a variety of environmental conditions. 2. ability to adhere to a variety of surfaces. 3. production of hydrolytic enzymes. 4. morphologic transition. 5. biolfilm formation 6. evasion and immunomodulation of the host defenses

Application of Biologic Principles: How effective is Clindamycin against E. Faecalis?

According to Skucaite, Enterococci spp. are 100% resistant to Clindamycin, though they are highly susceptible to erythromycin (90%).

Application of Biologic Principles: What is the mechanism of action for Penicillin?

According to Smith (1976): The penicillins have a killer part, and a modifier part. The killer part for all penicillins is the β-lactam ring. This ring acts as a bacterial analogue for a portion of the bacterial cell wall, thus weakening the wall and not allowing the cell to withstand the osmotic pressures of its environment. According to Cunningham: PCN is bactericidal, has low toxicity, and cleared renally. Broad Spectrum (kills both aerobes and anaerobes, G+ and G-.

Biologic Principles: True or False: Hydrocortisone decreases the level of bacteria in the periapical tissues of a necrosed pulp.

According to Smith et al (1976), False. Corticosteroids do not reduce bacterial counts, however it significantly reduces periapical inflammation.

Complications of Treatment: You just completed a root canal, with good length control, taper, and density. An appropriate build-up and crown were placed, and it can be assumed that the crown is well-sealed. At what time interval would you bring the patient back to re-assess periapical healing?

According to Sommer et al: 6 months. If there has not been any appreciable healing in 6 months, then surgery is indicated.

Treatment: What is the effect of post placement in abutment teeth for FPDs and RPDs, as wells as posts for single crowns? What about tapered cast posts vs. Para-posts with amalgam/resin?

According to Sorenson: Post placement increased the success rate of RPD abutment teeth (that needed endo) from 57% to 93%. Post placement did not increase success rates for FPDs. Post placement decreased success rates in single crowns. Tapered cast P&Cs had more failures than ParaPost with amalgam/resin.

Biological Principles: What type of sealer do you use? Give the components and Percentages of each. Are there toxic reactions to the sealer?

According to Spangberg (1973), everything is toxic. I have used Roth's sealer in the past: 42% ZnO as a filler/antimicrobial 27% Stabelite resin as an adhesive 15% BaSO4 as an opacifier 15% Bi subnitrate to decrease the setting time 1% Sodium borous anhydrous to increase the setting time.

Treatment: Maxillary RCT, will you use Articaine or Lidocaine to anesthetize?

According to Srinivasan: Articaine is better. According to Evans: Articaine is better in the anterior, but not the posterior. According to Kanaa (2012): there's no difference.

Treatment: How do you feel about using lasers in dentistry?

According to Stabholz, more research is needed, as the optimal wavelength for a uniform glaze of dentin without damage to surrounding tissues has yet to be found.

Etiology: What are the two most common types of bacteria found in endodontic infections, and what are their virulence factors?

According to Stephanopoulos (2004): 1. Gram (+) anaerobic cocci (peptostreptococcus species). 2. Gram (-) anaerobic rods (Prevotella and Porphyromonas species) Virulence Factors: 1. Superoxide Dismutase: allows them to tolerate oxygen up to 8% 2. Capsular polysaccharide: helps them avoid phagocytosis and induces abscess formation 3. Succynic Acid: helps to avoid phagocytosis 4. Endotoxin: cytotoxic 5. Proteolytic Enzymes: degrade tissues and promote bacterial invasion. 6. Hydrogen sulfide: cytotoxic

Etiology: What is the breakdown of inflammatory cells that are a part of a periapical granuloma/cyst?

According to Stern: 47% Macrophages 32% Lymphocytes 13% Plasma Cells 8% Neutrophils

Etiology: What are the four major categories that make up a periapical granuloma or cyst?

According to Stern: 49% Inflammatory Cells 40% Fibroblasts 6% Vascular Spaces 5% Epithelium

Pathogenesis: At what pH is E. Faecalis unable to survive?

According to Stuart (2006): pH 11.5 or greater. The proton pump found in E. Faecalis fights against this high pH.

Treatment: Does the placement of an amalgam core into canal spaces increase the resistance to fracture?

According to Summitt: Only if the coronal tooth structure is reduced to 2mm above the pulpal floor will the amalgam (extended 4mm into the canal space) provide extra resistance to fracture.

Pathogenesis: Describe the flora commonly present in failed endodontically treated teeth.

According to Sundqvist and Sjogren (1998), the microbial flora was mainly single species of predominantly gram-positive organisms. 38% of that population was e. faecalis.

Treatment/Pathogenesis: When treating a necrotic root canal, you decide to use a two-step method. Why is it important to place a medicament in the canal?

According to Sundqvist: -When you are instrumenting a necrotic canal, you are introducing oxygen into a low-oxygen environment, thus disrupting the conditions favorable to the anaerobic bacteria found therein. HOWEVER, if you don't place anything into the canal system other than a temporary restoration, you are closing it off to oxygen. Fluid can then leak into the root canal, thus providing a food source for the bacteria to thrive on. So...Sundqvist advocates putting a medicament (like calcium hydroxide) into a completely instrumented canal to dissuade bacterial propagation in-between appointments.

Pathogenesis: What are the three primary ecological factors that affect the growth of bacteria in endodontic infections?

According to Sundqvist: 1. Availability of nutrients 2. Low oxygen-tension in root canals with necrotic pulps. 3. bacterial interactions

Etiology: What strain of bacteria is typically associated with an actinomycosis infection?

According to Sundqvist: Actinomycis Israelii.

Complications of Treatment: How long will it take after losing a temporary restoration for saliva exposure to induce a significant microbial contamination?

According to Swanson & Madison: 3 days.

Complications of Treatment: a post-endodontic restoration is poorly sealed. How fast will bacteria travel to the apex of that tooth?

According to Swanson: as little as 3 days. According to Torabinejad: a poorly sealed crown has shown bacterial invasion in a little as 19 days. Certainly less than 30.

Diagnosis: What are some common radiographic findings that demonstrate a high likelihood of vertical root fracture?

According to Tamse (1999): - "Halo" lesions - perilateral radiolucency - angular resorption of crestal bone - diffuse or defined borders, but NOT corticated.

Diagnosis: What are some typical finding associated with vertical root fracture?

According to Tamse (2000): -V-shaped osseous dehiscence on the buccal plate (91%) vs. U-shaped, shallow, rounded, low-grade resoprtion in the palatal or lingual plate. - 9% buccal fenestration observed - wide bone resorption is indicative of a chronic VRF - narrow bone resorption indicative of an acute VRF Typical Symptoms: 1) chronic pain that is mild or intermittent to biting or purulent suppuration from sinus tract or osseous defect, 2) Acute or persistent pain, swelling or both, 3) exacerbation of chronic symptoms, or 4) asymptomatic.

Root Canal Anatomy: what key structure must you avoid when filing the canals of a maxillary first premolar?

According to Tamse: The palatal invagination of the buccal root. - Found in 97% of Max 1PM. This invagination started at the bifurcation site, progressed apically reaching a maximum of 0.40 mm at 1.18 mm from the bifurcation and then progressively got smaller and disappeared toward the apex. At the point of the deepest invagination, the dentin width was only 0.81 mm.

Treatment: You just resected a root apex and have exposed clean gutta percha. Can't you just heat that gutta percha and adapt it to the access opening?

According to Tanzilli (1980): That's a bad idea. The marginal adaptability of cold-burnished GP is more than 90% better than any of the other techniques investigated. Don't heat it. But, this is also why we don't just whack off the roots and walk away.

Treatment: You're placing a resin core after completion of RCT. Do you want a thick layer of adhesive or a thin layer?

According to Tay (2005): A thin layer. As the thickness of the adhesive is reduced, the volumetric shrinkage is reduced, which results in a reduction in shrinkage stress (S-factor).

Treatment: How does Resilon obturating material compare to traditional gutta percha?

According to Tay (2005): Resilon is susceptible to alkaline hydrolysis, and therefore microleakage. Resilon is no longer used.

Treatment: What's the best way to lute a fiber post to intra-radicular dentin?

According to Tay, a total-etch resin cement shows greater bonding potential than a self-etch or self-adhesive resin cement.

Medical History: what are the effects of long-term hyperglycemia?

According to Terezhalmy: -Tissue damage: micro/macrovascular disease and neuropathy.

Pathogenesis: what are the four stages of mucositis?

According to Terezhalmy: 1. Inflammatory/vascular 2. Epithelial 3. Ulcerative/bacteriological 4. Healing

Pathogenesis: What is a dead tract?

According to Trowbridge: An area of dentin that contains tubules that are devoid of odontoblast processes (the odontoblasts have been destroyed).

Complications of Treatment: What is the main goal of dental treatment for a patient who is about to begin chemotherapy treatment? How many days prior to chemo should a patient have teeth with questionable perio/restorative/endo prongoses extracted?

According to Terezhalmy: The goal of dental treatment is to intervene early (treat that incipient lesion) and aggressively prior to the onset of chemo treatment. Questionable teeth should be pulled at least 10 days prior to chemo. The reason: bacterial septicemias in immunocompromised patients are estimated to be caused by oral infection in up to 50% of the cases - especially periodontal disease and periapical pathology.

Anatomy: What is the embryologic origin of dental tissues?

According to Thesleff: The enamel stems from ectodermal tissues of the first branchial arch. Dentin, Cementum, pulp, and PDL are derived from Mesenchymal tissues of the neural crest.

Anatomy: How many dentinal tubules are located near the dentinocemental junction?

According to Tidmarsh (1989): 13,000 Anywhere from 19-48K close to the pulp.

Treatment: Which dental material provides the best seal: Amalgam, IRM, Super-EBA, or MTA?

According to Torabinejad (1995): MTA Kim (2005) confirms this: MTA>Super-EBA>Amalgam

Pathogenesis: What are the lymphoid organs?

According to Torabinejad: 1. Bone Marrow: production of lymphocytes 2. Thymus: production and selection of T-lymphocytes 3. Spleen: clears out old RBCs and other foreign bodies 4. Lymph Nodes: contain concentrated numbers of lymphocytes 5. Peyers's patches of the ileum (small intestine): lymphatic nodules that monitors and regulates intestinal bacterial populations

Complications of Treatment: You have a patient with a chronic apical abscess. Would you be worried about an allergic reaction to the abscess?

According to Torabinejad: Chronic apical lesions are well-localized and do not significantly increase the blood level of IgE, therefore an anaphylactic reaction is not going to happen. Disrupting the lesion via RCT will also not result in anaphylaxis.

Pathogenesis: what is a key component in the induction of the pulpal and periapical inflammatory response?

According to Torabinejad: LPS (endotoxin), which is produced by Gram (-) bacteria and induces cytokine production by host macrophages.This leads to pulpal and periapical inflammation. Gram (-) Bacteria genera of interest include: -Fusobacterium -Treponema *-Prevotella* *-Porphyromonas* -Tanerella -Dialister -Camphylobacter -Veillonella

Physiology: What is the purpose of prostaglandins:

According to Torabinejad: Prostaglandins promote the following: - GI homeostasis - Inflammation - Vasodilation - Chemotaxis - Pain - Vascular Permeability - Bone Resorption

Treatment: Describe the Passive Step-back Technique.

According to Torabinejad: Step 1 (Access): Access & completely unroof the pulp chamber and establish working length w/ a #15 file. Step 2 (Patency): Passive step-back hand instrumentation- A # 10 or 15 K-type file is placed to the radiographic apex with a light one eighth to one quarter turn and push-pull strokes to establish apical patency. With the same motion # 20-40 K-type files are carried into the canal as far as they can be passively inserted. Step 3 (Coronal Flaring): Passive use of Gates-Glidden drills- insert a #2 GG to a point where it binds slightly, pull back 1-1.5 mm, activate the slow-speed handpiece and plane the canal walls with an up and down motion. Irrigate then repeat w/ a # 3 GG to a shallower depth. Step 4 (Confirm WL): Confirmation of working length - radiographically or with an apex locator. Step 5 (More coronal flaring): Passive use of Gates-Glidden drills or Peeso reamers - #2 and #3 GG or Peeso reamer is used as in Step 3. Caution as the use of Peeso drills prior to initial coronal flaring can lead to excessive hard tissue removal and perforations. Step 6 (Obtain MAF): Apical Preparation-A #20 file should penetrate the full working length without any resistance. Prepare the canal with sequential use of progressively larger instruments placed successively further from the working length.

Treatment: can you place MTA as a retrograde restoration in the presence of blood?

According to Torabinejad: Yes, there can be blood in the canal space, and the MTA will still set and seal.

Pathogenesis: What is Replacement Resorption?

According to Tronstad: A secondary complication of widespread external inflammatory root resorption following extensive PDL loss as a result of traumatic dential injuries with resultant loss of the corresponding protective precementum and cementoblastic layer.

Objective Examination: How does the transfer of cold initiate an action potential when refrigerant is applied to a tooth?

According to Trowbridge (1980): When cold is applied to the tooth, the temperature drops, and dentinal fluid moves in an outward direction from the pulp. According to Brannstrom's Hydrodynamic Theory, this fluid movement stimulates the Aδ fibers that make up the Plexus of Raschow, and a pain response is initiated.

Pathogenesis: Chronic inflammation is a per[BLANK] inflammatory response.

According to Trowbridge: (Per)sistent.

Pathogenesis: List the four types of hypersensitivity.

According to Trowbridge: (a) Anaphylactic: (b) immune cytotoxic; (c) immune complex; (d) delayed.

Pathogenesis: How can lysosomal enzymes be released from neutrophils? How do they function as anti-inflammatory agents? How can they injure the host?

According to Trowbridge: (a) Death of the inflammatory cell (b) leakage of enzymes during formation of phagocytic vacuoles; and (c) reverse endocytosis. They are able to degrade substances that act as inflammatory stimuli. If released from the phagocyte they are capable of hydrolyzing components of host tissue.

Pathogenesis: When vascular permeability is increased, which plasma proteins may be found in the exudate?

According to Trowbridge: - Albumin (aids in maintaining osmotic pressure) - fibrinogen (key in the formation of a fibrin clot) - immunoglobulins (antibodies - immune response) - high molecular weight proteins (osmotic pressure)

Pathogenesis: What is the biologic activity of the following complement components and split products: C3a, C3b, C5a, C8, C9

According to Trowbridge: - C3a: anaphylatoxin - C3b: opsonization - C5a: anaphylatoxin, chemotaxin - C8: Cell lysis - C9: Cell lysis

Pathogenesis: What three mediator systems are associated with plasma proteases?

According to Trowbridge: - Kinin system, - Fibrinolytic system, -Complement system.

Pathogenesis: List as many acute phase proteins as you can. Try to remember how each benefits the host.

According to Trowbridge: -Ceruloplasmin-scavenges oxygen radicals generated by leukocytes. -Complement components C3, C4, and B. -Protease inhibitors-Recall that leukocyte proteases (eg, collagenase, elastase, gelatinase) could damage host tissue. APR proteins include anti-proteases, such as α1-protease inhibitor (α1-PI) , α-antichymotrypsin, and α2-macroglobulin, which have the ability to inhibit potentially injurious proteases. A congenital deficiency in α1-Pl can result in lung disease (emphysema) or liver disease (cirrhosis) due to the action of leukocyte elastase. -C-reactive protein (CRP)-can bind to bacteria and produce capsular swelling, precipitation, agglutination the bacteria. Binding also fixes complement, thus causing the production of C3b (an opsonin) and chemotactic factors. -Fibrinogen-is involved in blood coagulation and may serve as an opsonin by causing certain bacteria to clump together, notably staphylococci streptococci. Breakdown products of fibrinogen are thought to have inflammatory activity. -Transferrin-a major iron transport protein decreases, thus limiting the amount of iron available to meet bacterial growth requirements.

Pathogenesis: Name two important agents in opsonization.

According to Trowbridge: -Complement component C3b -opsonizing antibodies.

Pathogenesis: Name as many of the cytokines that are associated with bone resorption as you can. (1 start over, 2 you're awake, 3-genius, 4 you write the next edition!)

According to Trowbridge: -IL-1α -IL-1β -TNF-α -TNF-β .

Pathogenesis: Name at least three growth factors associated with wound healing.

According to Trowbridge: -Platelet-derived GF, -epidermal GF, -nerve GF, -macrophage-derived GF, -fibroblast GF

Pathogenesis: Name at least five major substances that have been shown to mediate increased vascular permeability.

According to Trowbridge: 1. Histamine 2. Kinins 3. Fibrin split products 4. Prostaglandins 5. Leukotrienes 6. Complement components C3a and C5a

Pathogenesis: Name as many mast cell degranulating agents as you can. Go!

According to Trowbridge: 1. Histamine 2. Serotonin 3. Proteoglycans 4. Tryptases 5. Carboxypeptidase A 6. Chymase 7. Renin 8. Prostaglandins 9. Cys-leukotrienes 10. Platelet activating factor 11. IL-4 12. IL-5 13. TNF-α 14. TGF-β 15. Chemokines

Pathogenesis: What role does tissue damage play in the activation of kinins?

According to Trowbridge: 1. Release of proteases such as trypsin and pepsin from injured cells. 2. Activation of Hageman factor. 3. Passages of prekallikrein into tissues. 4. Activation of plasminogen during blood clotting.

Pathogenesis: What are the general properties of chemotactic factors?

According to Trowbridge: 1. Stimulate direction of migration 2. Combine with receptor sites on the cell membranes of leukocytes. 3. Water soluble, diffusible. 4. Usually polypeptides or small proteins 5. Come from a number of sources, endogenous and exogenous.

Pathogenesis: In acute inflammation, what produces increased permeability of blood vessels?

According to Trowbridge: 1. Vasodilation 2. Intracellular gaps between endothelial cells. 3. Increased hydrostatic pressure in vessels. 4. Destruction of endothelial cells can also increase permeability (providing the basement membrane remains intact, otherwise there would be hemorrhage).

Pathogenesis: Name the three principal phenomena associated with the acute inflammatory response.

According to Trowbridge: 1. Vasodilation 2. Vascular Stasis 3. Increased vascular permeability

Pathogenesis: Full-blown AIDS usually develops when the lymphocyte count drops below [BLANK] cells/uL

According to Trowbridge: 200

Pathogenesis: Characterize the inflammatory cell infiltrate in periodontal disease.

According to Trowbridge: A chronic inflammatory cell infiltrate.

Pathogenesis: Characterize the inflammatory response that produces a pulp polyp.

According to Trowbridge: A chronic inflammatory response characterized by proliferation of chronic inflammation tissue.

Pathogenesis: What is a restriction element?

According to Trowbridge: A fragment of antigen that is combined with protein component of the cell membrane of an accessory cell.

Pathogenesis: What is the "secretory component" of IgA? What is its role?

According to Trowbridge: A glycoprotein synthesized by epithelial cells that combines with dimeric IgA. It facilitates transport of antibodies and protects against proteolysis.

Pathogenesis: What is a hapten?

According to Trowbridge: A non-antigenic small molecule that behaves as an anti- gen when combined with a carrier protein of the body.

Pathogenesis: What is granulomatous inflammation? What is the hallmark of granulomatous inflammation?

According to Trowbridge: A pattern of inflammation characterized by the presence of granulomas. Epithelioid cells within granulomas.

Pathogenesis: How are platelets involved in hemostasis? What components of platelets are capable of mediating inflammation?

According to Trowbridge: Accumulation of platelets results in formation of platelet plug. Platelets release clot-promoting factors and 5-HT, which causes constriction of small vessels area of hemorrhage. Serotonin (5-HT), histamine, prostaglandins, proteolytic enzymes, and cationic proteins.

Pathogenesis: How are non-sensitized T cells recruited to participate in immune reactions?

According to Trowbridge: Activated T lymphocytes release cytokines, which make non-sensitized T cells behave as though they were activated.

Pathogenesis: What causes the production of T-cell cytokines?

According to Trowbridge: Activation of T-effector cells.

Pathogenesis: Which cells serve as Class I antigen-presenting cells and to which cells do they present antigen?

According to Trowbridge: All cells except red blood cells. They present antigen to cytotoxic T cells.

Pathogenesis: which cells of the immune system are perturbed in AIDS?

According to Trowbridge: All cells of the immune system are adversely affected, directly or indirectly

Pathogenesis: What is edema?

According to Trowbridge: An abnormal amount of fluid in the tissue spaces.

Application of Biological Principles: How much do the following medications cost: -Metronidazole -Penicillin VK -Amoxicillin -Clindamycin -Augmentin -Azithromycin (Z-Pak)

According to Walmart Established Prices (March 2018, no discounts applied) on GoodRX.com -Flagyl (Metronidazole): $29.00 for 28 tabs. Accepted by most insurance plans -Pen VK: $41.00 for 40 tabs. Accepted by most insurance plans -Amoxicillin: $4.00 for #30 tabs. Accepted by most insurance plans -Clindamycin: $80.00 for 30 tabs. Accepted by most insurance plans. -Augmentin: $56.00 for 20 tabs. Accepted by most insurance plans. -Azithromycin (Z-Pak): $14.49 for one pack (6 tabs). Accepted by most insurance plans.

Application of Biologic Principles: How effective is a PDL injection, and is it safe for the periodontium?

According to Walton, the PDL injection was 92% successful overall after 2 attempts. He also found that repair of damage (which was minimal) to the periodontium was seen after 25 days.

Complications of Treatment: Define an endodontic flare-up.

According to Walton: An increase in pain, swelling (or both) occurring hours to days following NSRCT that prompts the patient to contact the doctor, who then approves a non-scheduled visit.

Treatment: What is the best anesthetic to use for an intra-pulpal injection?

According to Walton: The type of anesthetic is not important, it's the pressure gradient that will cause a transient ischemia of the pulp, resulting in loss of sensation.

Treatment: What is the success rate for intra-pulpal injections?

According to Walton: 92%

Treatment: When closing an access with Cavit, what is the minimum thickness needed to prevent microleakage?

According to Webber: 3.5mm

Pathogenesis: Will transient Internal Root Resorption progress in the absence of infection?

According to Wedenberg and Lindskog, no. Transient Internal Root Resorption occurs after sustaining dental trauma, but curiously it will not progress in when the pulp remains bacteria-free.

Pathogenesis: Are the bacteria found in sinus tracts typically the same or different than those found in the root canal?

According to Weiger: 75% of the time, they are the same bacterial species.

Treatment: In emergency cases, do you leave the tooth open, or keep it closed?

According to Weine (1975), close it up. Open teeth have a statistically higher incidence of exacerbations, and they need more appointments to complete treatment.

When using an IO injection, why do you inject distal to the tooth in question?

According to Weller: It's based on the distribution of the neurons. The more distal the injection, the higher the neuronal block.

Pathogenesis: What is Actinomycosis?

According to Wesley (1977): Actinomycosis is a fastidious, slow-growing, chronic suppurative infection, caused by actinomyces organisms.

Treatment: What is the best way to place your sealer just prior to obturation?

According to Wiemann & Wilcox: The method doesn't matter, it makes no difference.

Complications of Treatment: Why might a previously asymptomatic necrotic tooth have a flare-up after therapy is initiated?

According to Wittgow (1975), if the bacteria in the pulp chamber are instrumented (pushed) beyond the apex and into the alveolar bone.

Etiology: You have an intact tooth with pulpal necrosis as a result of bacteria. What type of bacteria would you expect to find in that pulp chamber?

According to Wittgow (1975), you will find 1-2 strains of bacteria, and they are almost always obligate anaerobes. The most commonly found species were: - bacteroides (now termed prevotella and porphyromonas) -Fusobacterium (Gram - rod, anaerobic) -Eubacterium (Gram +; has flagella if mobile) -Veillonella (Gram - Cocci) -Peptostreptococcus (Gram + cocci)

Application of Biologic Principles: You decide to mix some Super-EBA to use as a retrograde restoration. How thick should it be?

According to Yaccino (1999): The consistency of the material made no difference with regards to microleakage. So...don't stress about it. Just mix it so you can handle it, and go for it.

Diagnosis: How often are C-shaped canals identified in the Chinese population?

According to Yang & Yang: 5% incidence in the Chinese.

Etiology: What types of orthodontic movements are highly correlated with external inflammatory root resorption?

According to Zahrowski & Jeske (systematic review): -Intrusive -Rotational

Treatment: What are the properties of the ideal endodontic irrigant?

According to Zehnder: 1. Broad antimicrobial properties 2. Highly effective against anaerobic and facultative organisms 3. Inactivates LPS 4. Dissolves both vital and necrotic tissue 5. Either prevents formation of the smear layer or dissolves it once formed

Complications of Treatment: How does the surrounding tissue respond to corrosion of silver points that have extended beyond the apex?

According to Zmener (1985), the tissues respond by effectively marsupializing the the silver point via granulomatous tissue.

Application of Biological Principles: How do intra-pulpal injections work?

According to a hallmark study by Rosenberg (1975): anesthesia is a result of pressure transmitted from the solution rather than the anesthetic itself. This pressure results in a transient ischemia, not in necrosis. Walton verified Rosenburg's findings regarding pressure. According to Smith: it is very important to lodge the needle tip in the canal to prevent backflow (thus preventing the loss of pressure).

Treatment: Describe the Ochsenbein-Luebke Flap.

Advantages: 1. Excellent access and visualization. 2. No tearing or tension. 3. Good reference points for closure. 4. More room for curettage. 5. Maintains good blood supply. 6. Marginal gingiva undisturbed. Disadvantages: 1. Incision may cross bony defect. 2. Possible scar formation. 3. Cannot visualize the entire root. 4. Possible retarded healing of verticals.

Treatment: Describe the Gingival/Envelope Flap.

Advantages: 1. A gingivectomy can be performed. 2. Gingival levels can be changed. 3. Repositioning is simplified Disadvantages: 1. Flap difficult to reflect. 2. Tension on flap is excessive. 3. Gingival attachment is disturbed. 4. Reflection longer so more anesthesia needed. 5. Access and visualization are compromised.

Application of Biologic Principles: You keep saying that Ibuprofen is the best analgesic to take after having a root canal completed. Can you back that statement up?

According to the 2007 Oxford League Table of Analgesic Efficiency, Ibuprofen 600/800mg was the most efficient common OTC analgesic, with an NNT of 1.8 (NNT of 2 is the gold standard, which Ibu exceeds). For Comparison: *Ibuprofen 600 or 800mg: 1.8* *Diclofenac 100mg: 1.8* Celebrex 400mg: 2.1 *Oxy/APAP 5/500: 2.2* Oxycodone 15mg: 2.3 ASA 1200mg: 2.4 *Ibuprofen 400mg: 2.5* Naproxen (Aleve) 500 or 550mg: 2.7 Ibuprofen 200mg: 2.7 *Tramadol 150mg: 2.9* Morphine 10mg IM inj: 2.9 *APAP 500mg: 3.5* Celebrex 200mg: 3.5 APAP 600 or 650mg 4.4 ASA 650 + Codeine 60: 5.3 *codeine 60mg: 16.7*

Medical History: Your patient has had a joint replacement. Do you premedicate them with an antibiotic prior to RCT?

According to the 2012 Joint Statement of the ADA and AAOS (American Assoc. of Orthopedic Surgeons): Dental procedures are unrelated to prothesis infection, and therefore Abx prophylaxis does not reduce the risk of subsequent infection from a dental bacteremia.

Complications of Treatment: What is a post-op flare up? What are the etiologies of a flare-up?

According to the AAE: "an acute exacerbation of periradicular pathosis after initiation or continuation of root canal treatment." Flare-ups are typically multi-factorial, with with chemical, mechanical, and microbial components.

Application of Biologic Principles: Discuss nitrous oxide and pregnancy/lactation.

According to the FDA: Nitrous oxide should be avoided in the pregnant patient, but is safe to use with a lactating mother.

Treatment: How do you treat an Invasive Cervial Root Resorption lesion?

Accordiong to Heithersay: 1. Debridement of the resorptive defect. 2. Placement of glycerol on the gingival tissues 3. Application of 90% TCA (trichloroacetic acid) for 1-4 minutes, followed by copious irrigation. 4. Restore with a RMGI. *Surgical access to the lesion may be required.* *A root canal is indicated for the treatment of Heithersay Class II and Class III lesions.*

Treatment: What factors affect the negotiability of MB2 canals in maxillary molars?

Accoriding to Ibarrola (1997): Factors identified as interfering with the negation of MB2 canals: - accumulation of debris and sealer - Dentinal debris produced by pathfinding instruments. - anatomical variations - diffuse calcifications - pulp stones

Treatment: Who first described the crown-down technique?

Ace Goerig (1982) 1. Coronal Access 2. Radicular Access 3. Apical Instrumentation

Treatment: What is "Acoustic Streaming?"

Acoustic streaming is the result of ultrasonic vibration, which causes rapid fluid movement. This fluid movement induces shear forces on the canal walls, which leads to debridement. Acoustic streaming also leads to cavitation, which is the rapid vaporization of fluid and subsequent explosion of those bubbles, leading to a focused jet of fluid that causes damage to the surrounding environment. So... if you put an ultrasonic file down a canal that contains NaOCl and activate that file, it will oscillate, thus generated acoustic streaming and inducing shear forces. The acoustic streaming will lead to cavitation, which will cause demineralization of the root canal walls, thus allowing the irrigant to penetrate further into the dentinal tubules and reach the pathogens hiding in those spaces.

Treatment: Describe the Semilunar Flap.

Advantages: 1. Simple to incise and reflect. 2. Close proximity to the apex once reflected. 3. Minimal anesthesia needed. 4. Gingival attachment undisturbed. 5. Oral hygiene capability immediately. Disadvantages: 1. Minimal vision and access. 2. Possible incision over bony lesion. 3. Blood vessels may be severed. 4. Possible tearing of corners of flap. 5. Delayed healing.

Diagnosis: Which Anterior Crown Anomaly is more commonly found in the Chinese population?

Anterior Crown Group III (Dens Invaginatus) -Oehlers 1957.

Treatment: When is an emergency pulpotomy indicated? What are the advantages and disadvantages of doing an emergency pulpotomy

An emergency pulpotomy is indicated for an irreversibly inflamed pulp in a mature tooth, when a complete root canal cannot be done. Advantage: According to Asgary & Eghbal, pain relief following a pulpotomy was greater than with a full pulpectomy in vital cases. Disadvantages: According to Cvek, calcification, internal root resorption, and complete pulpal necrosis can occur following a pulpotomy.

Radiographic Examination: According to Gartner, what is the classic radiographic appearance of Internal Root Resorption?

An oval-shaped enlargement of uniform density within the pulp space.

Treatment: Rigid Splint or Physiologic?

Andreasen demonstrated that a true rigid splint does not improve periodontal healing, and can actually lead to ankylosis. Neaverth confirms this. Antrim recommended the use of 20-30 lb. monofilament fishing line as a suitable splint material.

Application of Biologic Principles: It is important to control hemorrhaging during apical microsurgery. How do your anesthetics assist with that?

Anesthetics contain epinephrine, which acts peripherally by constricting blood vessels. According to Buckley (1984): you will get half the amount of blood loss by using Lido with 1:50K epi when compared with the same anesthetic with 1:100K epi. *Note: the longer the surgical duration, the more blood loss is encountered. So, be efficient. Don't mess around.* *Gutmann confirms Buckley's findings (1996).*

Radiographic Interpretation: How many microSeiverts is a patient exposed to when a CBCT is taken?

Anywhere from 20-500 microSv, depending on the unit, voxel size, and FOV.

Application of Biologic Principles: What material do you use for apexification procedures? References? Differentiate between apexogenesis and apexification.

Apexification: the induction of apical closure of an immature tooth, in which the pulp is no longer vital, usually by the formation of osteocementum or similar hard tissue. Apexogenesis: an attempt to maintain the vitality of the pulp tissue to allow physiological strengthening and development the root. Apexification: I use MTA apical barrier technique. Whiterspoon (2008) 93.5% success, Hachmeister (2002) 4mm of MTA showed better displacement than 1mm MTA, although apical barriers leaked more than root-end fill (poor methods). Lawley and Schindler(2004): Ultrasonically placed MTA imporved seal and adding a bonded composite improved fx resistance. Holden(2008): MTA as an artificle barrier in teeth with immature apicies 85% healed

Application of Biologic Principles: List as many uses of calcium hydroxide as you can and provide authors for each use.

Apexogenesis- Cvek Apexification-Frank Direct pulp capping-Cox Indirect pulp capping-King Internal resorption (lat perf)-Frank Intracanal medicament-Bystrom, Sjogren Control periapical exudation-Heithersay Canal debridement-Hasselgren Apical plug to control obturation-Pitts External inflammatory root resorption-Tronstad, Foster Avulsed teeth-Tronstad, Trope Repair iatrogenic perfs-Heithersay Horizontal root fx -Cvek Root canal sealers-Hovland Vertical root fractures-Luebke

Pathogenesis: Describe Internal Root Resorption

As a result of pulpal inujury, some degree of partial coronal pulp necrosis occurs and induces inflammation of the remaining apical vital tissue. This inflammed tissue must abut an area of exposed dentinal tubules, secondary to loss of the protective pre-dentin and odontoblastic layer, for internal root resorption to occur. If the apical tissue necroses, the resorptive process stops. (From Endodontics Review: A Study Guide)

Application of Biologic Principles: What is a typical prescription for aspirin, where does it work, what does it do, and what are its complications?

Aspirin 325mg tabs Sig 1-2 tabs po q4-6h prn Analgesic: works peripherally to inhibit the formation of prostaglandins Anti-inflammatory: inhibits prostaglandin synthetase cyclo-oxygenase by acetylation of the active site to prevent the formation of arachadonic acid and therefore prostaglandins. Anti-pyretic: vasodilation of superficial blood vessels to increase heat dispersion Complications: inhibits platelet aggregation; increased bleeding time for the life of the platelet. 650mg of ASA doubles the bleeding time for 4-7 days. This can be a problem for patients who need surgery. Adverse Effects: GI irritation/bleeding, allergy, disturbance of hemostasis, nephropathy, liver toxicity in high doses, salicylism, teratogenic effects, exacerbation of Reye's Syndrome, drug interactions.

Treatment: What phase of NiTi is more elastic?

Austenite Phase. Martinsite is less elastic. You need a really hot temperature to convert Marinsite to Austenite phase. More heat than what is provided by a standard dental autoclave.

Medical History: Your patient has cirrhosis. What should you be careful of when prescribing?

Avoid anything that is metabolized in the liver.

Anatomy: of the axons entering the pulp space, what are the different types, and what is their prevalence?

Aδ Fibers: 13% C Fibers: 87%

Diagnosis: What fibers does an EPT stimulate?

Aδ fibers

Application of Biologic Principles: How do C fibers differ from Aδ fibers?

Aδ fibers are myelinated and respond to dentinal stimuli (they are the first line of notification. C-fibers are unmyelinated and respond to pulpal irritants as well as release neuropeptides (like Substance P)

Anatomy: what nerve fibers are responsible for dentin hypersensitivity?

Aδ fibers.

Pathogenesis: What is the cause of periapical pathosis? Can you name an article that supports your answer?

Bacteria and their byproducts are the cause of periapical pathosis, according to Moller (1981) and his study involving monkeys. devitalized teeth w/o exposure to oral flora had no inflammation, except for minor inflammation in areas where there was over-instrumentation. In the teeth exposed to the oral environment prior to being sealed, there was significant inflammation and apical resorption. There was an average of 8-15 bacterial strains identified. The most common were facultative anaerobes, *with the number of obligate anaerobes increasing from the initial to final sampling.*

Pathogenesis: According to Trope, what is a key etiological factor in endodontic flare-ups?

Bacteria.

Pathogenesis: Define Quorum Sensing. How does it differ from biofilms, and what advantages does it offer?

Bacterial cells form and release autoinducers. When you have several bacterial cells releasing these autoinducers, a minimum threshold concentration is reached, leading to an alteration in gene expression for the bacteria. Quorum sensing leads to the production of extra-cellular particles that allow a biofilm to exist. The biofilm produces a significant amount of water to allow the bacteria the opportunity for continued survival. Advantages of quorum sensing: - symbiosis - virulence - competence - conjugation - antibiotic production - motility - sporulation - biofilm formation Thus, bacteria that engage in quorum sensing are much more difficult to eradicate than are planktonic bacteria.

Application of Biologic Principles: An emergent endodontic patient presents to your office. You prescribe a single dose of Ibuprofen and send them on their way. Good idea, or bad idea?

Bad idea. McClanahan et al demonstrated that a single dose of pretreatment analgesia alone will not signficantly reduce post-op pain compared to the reduction in pain from endodontic treatment alone.

Objective Examination: who discussed referred odontogenic pain?

Bender

Etiology: Describe the histological criteria for periapical healing after endodontic treatment.

Bender (1966)-must consider clinical, histological and radiographic findings to assess success 1. Absence of pain or swelling 2. Disappearance of sinus tract 3. No loss of function 4. No evidence of tissue destruction 5. Radiographic evidence of eliminated or arrested area of rarefaction after interval of 6mo to 2 yrs Brynolf (1967) : Histo not correlate with radiography; 93% of "healed" lesion had inflamm at apex Green (1997): Histo found healed lesions had no inflamm 74% (contradicted Brynolf)

Treatment: Who was the first to advocate for the use of ultrasonics for root-end preparations?

Bertrand (1976)

Radiographic Interpretation: What is an ideal kVp range for your radiographic unit?

Between 65-75 kVp. This provides a good balance between high and low kVp.

Diagnosis: Is it a granuloma or a cyst?

Bhaskar: 48% Granulomas, 42% cysts, 7.5% other, 2.5% apical scar. Lalonde: 45% Granulomas, 44% Cysts, 11% Other Nair: 50% Granulomas, 35% Periapical Abscesses, 15% Cysts (9% True, 6% Bay). Nair contradicts Bhaskar and Lalonde, indicating that their large percentage of "cysts" were a misdiagnosis.

Pathogenesis: How does bisphosphonate-induced osteonecrosis of the jaw work?

Bisphosphonates rapidly bind to bone and are ingested by osteoclasts. They inhibit the activity of osteoclasts, thus limiting the progression of osteoporosis. However, when the activity of osteoclasts are too severely limited and/or impaired, dead and dying osteoclasts are not replaced and the capillary network in bone is not maintained. The destruction of the capillary network induces necrosis.

Radiographic Examination: What are the common uses for each radiographic modality in endodontic diagnosis?

Blicher et al: Endodontics Review 2016

Application of Biologic Principles: What determines the duration of action of a local anesthetic?

Both the ability of the local anesthetic to block sodium channels, as well as the presence of a vasoconstrictor.

Etiology: What is the most commonly accepted theory for dentinal hypersensitivity?

Brammstrom's Theory of Hydrodynamics

Complications of Treatment: What is Cyclic Fatigue?

Break in the middle due to excessive bending back and forth.

Complications of Treatment: What is torsional fatigue?

Breaking due to binding at the tip

Define: Effervescence

Bubble in liquid. Combining Glyde lubricant with NaOCl will produce effervescence.

Complications of Treatment: Hargreaves discusses some complications associated with the use of local anesthetic. What local anesthetic do you use that can cause both ionotropic and chronotropic suppression of the myocardium? What is the difference between ionotropic and chronotropic suppression?

Bupivicaine is known to do this. Ionotropic suppression of the myocardium is manifest by a decrease in the volume of blood pumped by each heartbeat. Chronotropic suppression of the myocardium is the decrease in the rate of heartbeats.

Radiographic Interpretation: How do you increase or decrease the penetrating power of your x-ray unit?

By adjusting the kVp (this will increase/decrease the wavelength. Shorter wavelength = increased penetrating power. Therefore, higher kVp = increased penetration to deep tissues = more grayscale and less contrast. In other words, changing the kVp will determine the quality of the image that you're taking. Thicker structures (like #18 or #31 embedded in the thickest portion of the mandible) will require deeper penetration, therefore a higher kVp is required.

Treatment: What did Allison & Walton demonstrate with regards to cold lateral condensation?

By shaping the canal system to allow the spreader to reach within 1mm of working length, you can achieve a better obturation and a better seal while doing cold lateral condensation. *Spreader wide. Spreader deep.*

Medical History: How does a physician measure the long-term stability of a diabetic patient?

By taking a blood sample and identifying the HbA1C levels. HbA1C = glycosylated hemoglobin Normal A1C: 4-6% Target A1C for diabetics: < 6.5-7%, with a range of 6-8%. Uncontrolled diabetes has been known to reach 20%.

Radiographic Examination: Estrela, Azevedo 2008

CBCT is an accurate diagnostic method for identifying apical periodontitis. 20% more effective than traditional radiographs

Radiographic Interpretation: What is the difference between CCD sensors and CMOS sensors?

CCD= charged coupled device, which is essentially a scintillation layer laid over the electronic chip. It utilizes a "bucket brigade" approach to convert analog information to digital, which is processed and an image is recorded on the computer. CMOS= Complementary Metal Oxide Semiconductor. CMOS sensors have an active transistor at each element location.

Objective Examination: What pulpal sensitivity test would you expect to be more reliable when testing a calcified tooth, and why?

Calcified teeth have less/no fluid in the dentinal tubules, therefore thermal testing is less effective as it relies on that fluid movement to stimulate nerve fibers. EPT is more reliable because it induces ionic changes to activate the sodium channels.

Prognosis: According to Gorni and Gagliani (2004), what is the overall success rate for endodontically retreated teeth in which the canal morphology is respected, and the success rate in which it is altered

Canal Morphology respected: 87% Canal Morphology altered: 47% *40% Differential!!*

Medical History: What are the cardinal symptoms of Diabetes, and are they more common in Type 1 or Type 2?

Cardinal Symptoms: 1. Polydipsia (excessive thirst) 2. Polyuria (large production of urine) 3. Polyphagia (excessive hunger) 4. weight loss 5. loss of strength More commonly seen in Type 1 than Type 2

Complications of Treatment: How do you improve the fracture resistance of immature endodontically treated teeth?

Carvalho (2005): root reinforcement with fiber post or composite increases structural resistance. Wilkinson and Kirkpatrick (2007): self cured composite resin significantly increased fx resistance of the teeth.

Etiology: What is the difference between an alveolar dehiscence and a fenestration?

Dehiscence: an opening of the bone, which implies that it originates at the alveolar crest. Fenestration: latin is fenestra, meaning window. A Fenestration is a window opening in the bone, implying that the alveolar crest is not involved.

Medical History: What risk is assumed when a patient takes Ibuprofen in the final trimester of pregnancy?

Delayed childbirth.

Etiology: How long does it take for bacteria to infect a root canal in the presence of a break in a coronal seal?

Depends on who you read. Torabinejad and Kettering: 19 days Magura et al: ReTx recommended if the canal is exposed to the oral cavity for at least 3 months *Khayat and Torebinejad: average of less than 30 days*

Medical History: what is the most important thing you can do for the anxious patient?

Develop trust.

Radiographic Examination: Brynolf (1970)

Diagnostic accuracy increased from 74% to 90% when using additional radiographs taken from multiple angles

Diagnosis: What is diploplia?

Double-vision

Radiographic Interpretation: Who was the first one to call attention to the use of radiographs for the evaluation of root canals?

Dr. Westin A. Price. He is also credited with developing the bisecting angle technique

Etiology: According to Baumgartner, what is the most commonly found species in persistent endodontic infections?

E. Faecalis. E. Faecalis is resistant to calcium hydroxide at a pH of 11.1 but not at a pH of 11.5. E. Faecalis has a proton pump that allows it to decrease the pH. Chlorhexidine is an effective medicament against E. Faecalis.

Radiographic Examination: Define "Effective Dose."

Effective Dose is a calculation that takes into consideration the different sensitivities of organs to long-term effects from ionizing radiation. It is the preferred method for comparing doses between different types of exposures. We measure these values in micro-Seiverts. Average daily background radiation: 8.2-16.4

Radiographic Interpretation: What type of radiation do our tubeheads generate, particulate or electromagnetic?

Electromagnetic. Particulate Radiation: - Alpha or Beta rays - solid, subatomic particles that are charged Electromagnetic Radiation: - formed of units of pure energy that form waves due to electric and magnetic forces - generated when the velocity of an electrically charged particle is altered (ie. changing the speed of an electron will produce energy in waveform)

Prognosis: Tell me about the Washington Study

Epidemiological Study Ingle (1985) (only 33.41% of pts returned for recall) Success rate at 2 years: 94% Success Rate at 5 Years: 93%. Most common reasons for failure: - incomplete obturation: (59%) - perfs: (10%) did not consider poor C&S

Complications of Treatment: You are treating a diabetic patient and have injected an anesthetic containing epinephrine. What should you be conscious about with regards to this procedure?

Epinephrine counteracts the effects of insulin. In other words, more glucose is retained in the blood. This can lead to HTN, so use caution in patients that already have HTN, or a history of MI or cardiac arrhythmias.

Treatment: Discuss the Law of Symmetry 1

Except for maxillary molars, the orifices of the canals are equidistant from a line drawn in a mesial distal direction through the pulp-chamber floor.

Complications of Treatment: Goodacre discusses complications of various fixed prosthodontics restorations. Discuss.

FPD: 27% average will have complications - Caries: 18% - Need for Endo: 11% - Loss of retention: 7% - Esthetics: 6% - Peridontal Dz: 4% - Tooth Fx: 3% - Prosthesis Fx: 2% - Porcelain Veneer fx: 2% Resin-bonded Prostheses: 26% average will have complications - Debonding: 21% - Tooth discoloration: 7% - Porcelain Fx: 3% Single Crowns: 11% average will have complications. - Need for Endo: 3% - Porcelain Fx: 3% - Loss of retention: 2% - Periodontal Dz: 1% - Caries: 1% Posts and Cores: 10% average will have complications. - post loosening: 5% - root fx: 3% - caries: 2% - Periodontal Dz: 2% All-Ceramic Crowns: 8% Average with have complications - Fracture: 7% - Loss of retention: 2% - Need for Endo: 1% - Caries: 1%

Pathogenesis: According to Stefanopoulos, what types of organisms are dominate in the initial phase of abscess formation?

Facultative anearobes. Strict anaerobes are more dominant as the abscess matures.

Treatment: True or False: RCT dessicates dentin, thus weakening the tooth. Posts therefore serve to reinforce the tooth.

False. According to DeCleen, the hardness of dentin in unaffected by RCT, and the preparation for a post actually weakens the tooth.

Treatment: T/F: When creating a rectangular flap, you want the height of the flap to be twice as long as the length.

False. According to Velvart and Peters, you want the length to be double the height.

Etiology: True/False: Anaerobes are usually the primary pathogens in an endodontic infection.

False. According to Farber & Seltzer (1988), anaerobes are not usually the primary pathogens. They are usually secondary invaders spreading beyond the confines of the pulp and periapex.

Treatment: What is a resistance-type apex locator?

First generation apex locator (Neosono). When a lip clip is in place and a file is advanced into a canal, the circuit is completed when the tip touches periodontal tissues. The electrical resistance of the apex locator and the resistance between the file and oral mucosa are equal; this is indicated on the machine. Perforations can be detected with these units. Use is contraindicated in patients with cardiac pacemakers due to the constant electrical charge produced by the unit.

Pathogenesis: What is an immunoglobulin, and what types of immunoglobulins are found in periapical lesions?

From Baumgartner: An immunoglobulin is produced by a plasma cell specifically for the antigen that stimulated the precursor B cell. IgG>IgA>IgE>IgM

Anatomy: where does the dental pulp originate?

From the dental papilla

Complications of Treatment: what is the overall incidence of endodontic flare-ups?

Generally, the literature supports an incidence of less than 5%. Walton & Fouad: 3.17% (larger sample size) Walton & Chiappinelli: 1.3% Eleazar: 3% (single-visit) - 8% (multi-visit) Reader & Pickenpaugh: 10% (small sample size) Walton: 1.5-5.5% Iqbal:0.39% Mor: 4.2%

Objective Examination: Describe both the Glickman and Miller classifications for tooth mobility.

Glickman Classifications: +1: just beyond physiologic +2: < 1mm horizontal movement +3: > 1mm horizontal movement, possible rotation or depressability Miller Classifications: Class I: horizontal movement < lmm Class II: horizontal movement >1mm Class III: horizontal movement >1mm and/or depressable

Complications of treatment: You want to complete an orthograde root canal, knowing that this tooth will likely need a root end resection. You have a brilliant idea: why don't I just obturate with MTA, then when I go to do the surgery, I won't need to retrofill at that time. Good idea, or bad idea?

Good idea! According to Torabinejad (2002): Resecting MTA will not affect its ability to prevent microleakage. Just make sure you place enough MTA apically so there will be at least a 3mm plug after the resection (per Kim).

Prognosis: How does the Length of Obturation affect the success of endodontic treatment?

Grahnen and Hansson (1961): - Teeth overinstumented and overfilled failed more than underfilled teeth Seltzer and Bender (1963): - Underfilled (87%) - Flush (86.5%), - Overfilling (71%) Sjogren et al (1990): - Obturation 2mm short: 94%, - Overfills: (76%) - More than 2mm short: (68%) Schaeffer and Walton (2005): Meta-analysis 0-1 mm short better than 1-3 m short; both better than beyond apex

Pathogenesis: According to Siqueira, what type of bacteria are typically present in a persistent endodontic infection (ie. after initial treatment has been completed)?

Gram (+) bacteria. His study suggests that they are capable of adapting to harsh environmental conditions in instrumented and medicated root canals. E. Faecalis is a Gram (+) facultative anaerobe from the enterococcus family, and is the most common enterococcus bacteria identified in previously obturated root canals with persistent infection. Molander identified Enterococci present in 78% of these cases. Sundqvist noted that in 80% of these cases, a single strain of bacteria was present, and 90% of the time it was E. Faecalis

Etiology: What are the four major categories of microbes?

Gram + Cocci Gram + Rods Gram - Cocci Gram - Rods

Etiology: What is the difference between Gram + and Gram -?

Gram + and Gram - is simply a difference in the way a bacterial cell wall stains. +/- stain in differing ways because of the different structures found within their walls. This is significant because if we know what their wall is made of, we can have a better idea of how to lyse that wall, thereby destroying the cell. Gram - walls are typically thinner than Gram +, and contain LPS (also known as endotoxin). This endotoxin is important in the process of pulpal inflammation, often initiating odontoblastic response prior to the arrival of the bacteria proper. Gram + cell walls contain a thick peptidoglycan layer, which retains the violet Gram stain much better than the thinner Gram - cell walls.

Application of Biologic Principles: You're obturating with "gutta percha" cones. What are those cones made from, and how do they work?

Gutta Percha: Trans-isoprene (chemically related to natural rubber latex Composition of cones: - 65% Zinc Oxide - 20% Gutta Percha - 15% Waxes, resins, metals Starts out in the β-crystalline phase, when heating it transforms to the α-crystalline phase.

Anatomy: What is HERS, and what does it do?

HERS stands for Hertwig's Epithelial Root Sheath, and it is formed by the inner and outer enamel epithelium. This in turn activates the mesenchymal cells to become odontoblasts and produce root dentin.

Medical History: What is the difference between HIV and AIDS?

HIV: Human Immunodeficiency Virus. This is defined as a patient with a CD4 lymphocyte count between 200-500. AIDS: Acquired ImmunoDeficiency Syndrome. This is defined as a patient with a CD4 count less than 200. A patient without HIV/AIDS has a CD4 count between 500-1500.

Application of Biologic Principles: Tell me about Triazolam.

Hargreaves and Dionne discussed this in detail. Here are the essentials: 1. administered orally in 0.125mg, 0.25mg, or 0.50mg doses. Standard is 0.25mg, 0.125mg in older patients. 2. Rapid onset of 30-60 minutes 3. Half-life of 90 minutes, with complete recovery in 2 hours 4. Inactive metabolites 5. Anxiolytic 6. Amensic 7. Use a pulse ox and get pre and post-op vitals. 8. 50% nitrous with the use of .50mg of Triazolam increases the recovery time. 9. No respiratory depression at maximum clinical doses. 10. Sub-lingual administration increases the bioavailability of the drug by 28% 11. Binds to Benzo receptors on post-synaptic GABA neurons in the CNS, increasing the neuronal membrane permeability with respect to the chloride ion, leading to hyperpolarization (not easily excitable), and thus CNS depression 12. Schedule IV drug

Treatment: Who would you consider to be the biggest name to remember with regards to using full-strength NaOCl as an irrigant?

Harrison

Radiographic Interpretation: what is the by-product of x-ray photon production via an electromagnetic field?

Heat

Pathogenesis: Describe Invasive Cervical Root Resorption.

Heithersay is the big name to remember here, he did the landmark studies with regards to this type of resorption. For ICRR to occur, the PDL must be in direct contact with dentin. The PDL tissues have the potential for inflammatory invasion, which will occur if there is a developmental or iatrogenic defect in the cementum or or cementoid layer of the root.

Radiographic Interpretation: You use a higher Kv (kilovoltage) setting to take your radiographs. What can you expect?

Higher Kv leads to more excited electrons, therefore higher energy photons. These photons will lead to less absorption in soft tissue and hard tissue. The imaging result is more grayscale and less contrast. The Good: less soft tissue radiation, which is non-diagnostic and therefore of no clinical value. More grayscale is picked up, so you have a wide range of tissue to look at. The Bad: It can be more difficult to delineate between structures (ie. you won't be as likely to pick up on incipient lesion changes...or perhaps periapical lesion changes).

Diagnosis: What is another name for a pulp polyp?

Hyperplastic pulpitis.

Treatment: What do you use as a solvent for the removal of gutta percha from a canal, and do you have any concerns about its use?

I use chloroform to dissolve the gutta percha. McDonal and Vire (1992) demonstrated a minimal health hazard to airborne chloroform in the operatory. While some solvent is extruded through the apex of the tooth, Chutich (1998) demonstrated that the amounts are well below the permissible amount, and therefore do not pose a health hazard to the patient when properly used. Finally, Baumgartner (2006) recognized that the use of chloroform in retreatment cases possesed and antibacterial activity that significantly reduced the intra-canal levels of e. faecalis.

Treatment: What types of irrigant do you use, and why?

I use two main irrigants: 1. NaOCl 2. EDTA According to *McComb & Smith* (1975): 1. NaOCl is the best irrigant for the removal of organic debris. 2. EDTA was the best irrigant for removing the smear layer (ie. mostly inorganic material).

Application of Biologic Principles: What is a typical prescription for Ibuprofen, where does it work, what does it do, and what are its complications and adverse effects?

Ibuprofen 800mg Sig 1 tab TID prn pain. Anti-inflammatory: inhibits prostaglandin synthetase cyclo-oxygenase by acetylation of the active site to prevent the formation of arachadonic acid and therefore prostaglandins. Adverse Effects: nausea, epigastric pain, heartburn, dizziness, skin rash. Do not prescribe to pregnant women.

Application of Biologic Principles: Why is it not a good idea to prescribe Ibuprofen to asthmatics?

Ibuprofen is a Cox-2 inhibitor. When this happens in the asthmatic, the production of arachidonic acid shifts to the Lipoxygenase pathway, which can trigger an asthmatic attack. It is therefore contraindicated.

Pathogenesis: what types of systemic reactions are associated with the four main immunoglobulins found in periapical lesions?

IgG: protects against bacterial and viral infections (most prevalent) IgA: associated with mucous membranes IgE: Allergic Reactions (anaphylaxis) IgM: First responder. Found in blood and lymph fluid (least prevalent) Source: Baumgartner

Root Canal Anatomy: Describe the classic study by Pineda & Kuttler.

In 1972, Pineda and Kuttler completed a radiographic examination of root canals. Summary: 7275 root canals were broken down into three groups by age: <25yo, 35-45yo, >55yo. Then they radiographed them in two planes (BL and MD), and their anatomies were analyzed. Data: 83% of apical foramina were NOT located at the anatomic apex (sometimes 2-3mm to one side. Only 3.1% of canals were straight in both the MD and BL planes. This study revealed what we now call the "fast break" radiographically. The canal disappears half-way down the root, indicating that there are two canals present at that location.

Radiographic Examination: What is the Underwood Septum?

It is the septum that is located within the maxillary sinus, and can most readily be viewed on a panoramic image.

Root Canal Anatomy: Describe Vertucci's classic study.

In 1984, Vertucci completed an in-depth study of root canal anatomy of human permanent teeth. Summary: A total of 2400 extracted permanent teeth were decalcified, injected w/ dye, cleared and evaluated for root canal anatomy including the number of root canals and their types, location of foramina, and frequency of deltas. Data: MB2 present in 55% of Max 1st Molars, 29% of Max 2nd Molars. Most lateral canals are found in the apical third of the root Apical foramina located laterally 75% of the time. 62% of Max 1st premolars were Vertucci Type IV (Weine Type III) Transverse anastamoses were found most often in the middle third of the roots. Note: Most of these teeth studied came from North Americans. Teeth vary by demographic. Similar studies by Pineda & Kuttler (radiographic) and by Okumura (transparent specimens)

Treatment: Describe the ideal post.

In my opinion, one that's not there. But if you have to use one... According to Goerig: 2/3 the length of the root and leaving 4-5mm of gutta percha at the apex.

Application of Biologic Principles: When are benzodiapenes contraindicated?

In patients with: - hypersensitivity - significant psychiatric history - narrow-angle glaucoma - use of other CNS depressants -Pregnancy/breast-feeding

Treatment: Al-Omiri discusses fracture resistance with regards to post-retained restorations. Summarize.

Increased post length = increase fracture resistance. Increased post diameter = decreased fx resistance. Tapered metal posts = greater cervical stress Parallel-sided posts = greater apical stress Cast metal post = greater fx resistance, greater catastrophic failures Intimate post fit = greater resistance Ferrule = a very good thing Luting cement: adhesives allowed for even stress distribution = greater fx resistance. Coronal Coverge: crowns with good ferrule = increased fx resistance. More remaining tooth structure = increased fx resistance. No remaining wall + fiber post≠ increased fx resistance

Treatment: what is the technique of choice for delivering anesthesia to posterior teeth?

Inferior Alveolar Nerve Block

Pathogenesis: What is the common pathogenesis component of each type of resorption?

Inflammation

Pathogenesis: Describe Innate Immune Response, Adaptive Immune Response, Humoral Immune Response, and Cellular Immune Response.

Innate Immune Response: an important subsystem of the overall immune system that comprises the cells and mechanisms involved in the defense of the host from infection by other organisms. The cells of the innate system recognize and respond to pathogens in a similar way, but, unlike the adaptive immune system, the system does not provide long-lasting immunity to the host.[2] Innate immune systems are the first and immediate line of defense against infection, all classes of plant and animal life are endowed with. The major functions of the vertebrate innate immune system include: Recruiting immune cells to sites of infection through the production of chemical factors, including specialized chemical mediators called cytokines Activation of the complement cascade to identify bacteria, activate cells, and promote clearance of antibody complexes or dead cells Identification and removal of foreign substances present in organs, tissues, blood and lymph, by specialized white blood cells Activation of the adaptive immune system through a process known as antigen presentation Acting as a physical and chemical barrier to infectious agents. Adaptive Immune Response: a subsystem of the overall immune system that is composed of highly specialized, systemic cells and processes that eliminate pathogens or prevent their growth. Adaptive immunity creates immunological memory after an initial response to a specific pathogen, and leads to an enhanced response to subsequent encounters with that pathogen. This process of acquired immunity is the basis of vaccination. Like the innate system, the adaptive system includes both humoral immunity components and cell-mediated immunity components. Humoral Immune Response: the aspect of immunity that is mediated by macromolecules found in extracellular fluids such as secreted antibodies, complement proteins, and certain antimicrobial peptides. Humoral immunity is so named because it involves substances found in the humors, or body fluids. Cellular Immune Response: an immune response that does not involve antibodies, but rather involves the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to an antigen.

Pathogenesis: What is the difference between Innate Immunity and Adaptive Immunity?

Innate immunity involves cells that are inherently present in the injured tissue and are non-specifically targeting foreign bodies and injured tissue. Adaptive immunity is fighting specific antigens. Innate Immunity: - Physical Barriers - Phagocytes - Inflammation - Non-specific proteins - PMN leukocytes - Mononuclear cells - Natural Killer Cells - Mast cells - Basophils Adaptive Immunity: - B-Cell responses - T-Cell responses

Medical History: What is insulin shock, and what are the signs and symptoms associated with each stage?

Insulin shock: The diabetic patient forgot to eat, but took their insulin. This increases the absorption of glucose from the blood, resulting in hypoglycemia. There are three stages to Insulin Shock: Mild: Hunger, weakness, tachycardia, pallor, sweating, paresthesias Moderate: Incoherence, uncooperativeness, belligerence, lack of judgement, poor orientation Severe: Unconsciousness, tonic/clonic movements, hypotension, hypothermia, rapid thready pulse

Treatment: In what situation is the Akinosi injection useful?

It can be administered in the presence of trismus.

Medical History: why is dexamethasone use inadvisable for diabetic patients?

It can cause hyperglycemia. (It's a glucocorticoid)

Application of Biologic Principles: Is Ibuprofen safe to give a pregnant woman?

It depends on which trimester she is in. For the first two trimesters, the drug is a Pregnancy Risk Category B (safe to use, but no adequate human studies to confirm). In the third trimester, it is Category D (there is a risk to the fetus, but circumstances may outweigh those risks). APAP is a complete Category B, and is therefore a safer (albeit less effective) option. *Common dental antibiotics are Category B, and are safe to use on the lactating mother.*

Define: Dysesthesia

It is defined as an unpleasant, abnormal sense of touch. It often presents as pain but may also present as an inappropriate, but not discomforting, sensation.

Treatment: What is the proper way to achieve good hemostasis for apical surgery?

It starts before the procedure begins, with your anesthetic. According to *Kim* (1997): *Presurgical:* -give 2 to 3 carpules of 1:50,000 epinephrine local anesthetic using multiple infiltration sites throughout the entire surgical field. *Surgical:* -Remove all granulation tissue, place an epinephrine pellet into the bony crypt followed by dry sterile cotton pellets; -apply pressure for 2 minutes and remove all the cotton pellets except the first epinephrine pellet. -Continue with the procedure and remove the epinephrine pellet before final irrigation and closure. -Alternatively, calcium sulfate can be mixed into a thick putty and packed against the bony cavity; this is especially useful in large or through-and-through lesions. -Small bleeding sites in the bone can be brushed with ferric sulfate solution. *Postsurgical:* Tissue compression before and after suturing decreases postsurgical bleeding and swelling. According to Niemzyck: *Give slow injections.* *Delay your incision for a solid 10 minutes.* *It's usually impossible to re-establish hemostasis by addtional injections.*

Radiographic Interpretation: Describe the Periapical Scoring Index System (PAI).

It was developed by Orstavik in 1986. Scores radiographic periapical lesions from 1-5 1: Healthy; normal periapical structures 2: Small changes in bone structures 3: Change in bone structures with mineral loss 4: Periodontitis with well-defined radiolucent area. 5: Severe periodontitis with exacerbating symptoms

Application of Biologic Principles: What is Percodan?

It's a combination of Percocet with aspirin instead of acetaminophen.

Application of Biologic Principles: What is the mechanism of action for Acetaminophen?

It's not completely known. However... According to the proposal by Yagiela: It inhibits prostaglandin formation and interacts with both the cannabinoid and serotonergic systems.

Application of Biologic Principles: What is it about a local anesthetic that determines its potency?

Its lipid-solubility. The more lipid-soluble, the more potent.

Medical History: Your patient is breastfeeding. When would be the best time for her to take a prescribed medication?

Just after feeding.

Hierarchy of Evidence: What is a randomized controlled trial?

LOE: 2. A study that involves a planned intervention of a diseased population. It is the second highest level of evidence according to the Oxford Centre for Evidence Based Medicine.

Hierarchy of Evidence: What is a Cohort Study?

LOE: 3. A study that investigates the causes of disease, establishing links between risk factors and health outcomes. They are typically prospective (forward-looking, ie. carried out over a future period of time).

Hierarchy of Evidence: What is a Case Control Study?

LOE: 4. An observational study in which two existing groups differing in outcome are identified and compared on the basis of some supposed causal attribute.

Hierarchy of Evidence: What is a Case Series?

LOE: 5 A study that presents and outcome based on subjects with a known exposure. There are no controls in this study.

Hierarchy of Evidence: What is an Expert Opinion

LOE: 6. Some doctor spouting off something they think they know about, but really have no reliable data or proof to back it up. This is great for generating questions and hypotheses.

Diagnosis: That periapical lesion, what is it?

Lalonde: 45% Granulomas 44% Cyst Bhaskar has similar numbers Nair contradicts Lalonde & Bhaskar: 15% Cysts (9% True, 6% Bay)

Diagnosis: Who supports the findings of Seltzer and Bender regarding the definitive lack of histologic/clinical correlationship, and who refutes it?

Langeland (1977) supported the lack of correlation between clinical signs and symptoms and histopathological findings. Ricucci and Siqueira indicated a high correlation between normal/reversible pulps and their histologic findings.

Pathogenesis/Etiology: You notice a PARL on #13, and the diagnosis is Pulp Necrosis/Asymptomatic Apical Periodontitis. Where is the bacteria located?

Langeland studied 35 periapical lesions and found that these lesions tend to be sterile. Take Home: the lesion is almost entirely inflammatory in nature, limiting the bacteria to the canal spaces when it is not an abscess. Walton: inflammatory lesions tend to resist the spread of bacteria, thus confining them to the canal space. Important to note: Bacteria was found in refractory (persistent) periapical lesions (ie NSRCT already completed) 88% of the time (Iwu; Wayman). Of these persistent bacteria, Porphyromonas spp. and Prevotella spp. are not frequent. Gram + species are typically responsible for acute symptoms of refractory lesions.

Radiographic Examination: According to Ee, B Johnson et al (2014), what has been the effect of CBCT on endodontic diagnosis and treatment planning?

Pre-operative CBCT imaging provides additional information when compared with preoperative PAs, which may lead to modifications in the treatment plan 62% of the time.

Radiographic Examination: You have a radiographic periapical lesion. Can you tell if it is a granuloma or a cyst?

No. The histology of a lesion cannot reliably be predicted by a radiograph. HOWEVER... According to Lalonde's study, if a radiographic lesion measures at least 16mm+ in diameter (in any direction), it is more likely to be a cyst rather than a granuloma.

Medical History: your patient is on an anti-coagulant medication. What would be a good INR for this patient who requires a dental surgery?

Less than 3.5 is needed for most surgeries. For endodontic surgery, you will want it lower due to the need for a dry field. Something lower than 3.0 is ideal for endodontic surgery.

Medical History: Your patient has COPD. What oral manifestations might they present with? What precautions should you take?

Leukoplakia, erythroplakia, SCCa in chronic smokers. Precautions: - use an upright position to treat them whenever possible. - Low-flow Oxygen is indicated - No narcotics or antihistamines

Medical History: your patient has a history of seizures. What dental precautions should you take?

Ligate everything you can (RD retainer, bite block, etc).

Pathogenesis: According to Tronstad, what must occur for resorption to take place?

Loss or damage of the protective, unmineralized layers of the tooth apparatus.

Pathogenesis: What is significant about Streptococci (facultative anaerobes) being able to bind to Type 1 Collagen?

Love demonstrated that facultative anaerobes can compete for invasion of dentinal tubules by being able to bind to Type 1 Collagen (found in dentin). This is significant because it allows for a food source for the bacteria, thus facilitating its survival. e. Faecalis can bind to Type I Collagen.

Radiographic Interpretation: You use a lower Kv (kilovoltage) setting to take your radiographs. What can you expect?

Lower Kv leads to less-excited electrons, which will produce lower-energy photons. This leads to less overall radiation produced at the tube head, which means you would likely have to increase the exposure time in order to get a diagnostic radiograph. This will lead to a higher soft tissue (superficial) radiation, and lower hard tissue (deep) radiation. The result is an image with greater contrast, and therefore fewer grayscales. The good: what you can see, you can readily tell the difference between different structures (like a changing incipient lesion). The bad: You can't see much.

Pathogenesis: What are lymphocytes?

Lymphocytes are white blood cells that assist in the immune response. There are two types of lymphocytes: T cells and B Cells T Cells: seek out and destroy human cells that are defective (i.e. cancer cells or infected cells) B Cells: produced to respond to specific antigens. When activated, they rapidly divide and become plasma cells, which produce antigen-specific antibodies.

Pathogenesis: What are macrophages?

Macrophages are phagocytic cells that trap antigens in local lymph nodes. They also engulf foreign bodies and immune complexes

Prognosis: According to Sjogren and Sundqvist (1990): what is the decisive factor for determining the outcome of endodontic therapy?

Pre-operative periapical status.

Pathogenesis: What is "microbial Succession," and who coined the term?

Microbial succession, as described by Fabricious et al, is the process whereby bacteria in a primary infection progresses from a largely aerobic species to an anaerobic species.

Medical History: Your patient is taking an ACE-inhibitor for HTN. What can you give them to manage their post-op endodontic pain?

NSAIDS can be used, but not for prolonged periods, as their use can decease the anti-HTN effects of ACE-inhibitors.

Medical History: what is the concern of prescribing narcotics to a pregnant woman?

Neonatal respiratory depression

Medical History: What are the updated categories for hypertension, according to the American College of Cardiology and the AHA.

New Categories: Normal: <120/80 Elevated: 120-129/<80 Stage 1: 130-139/80-89 Stage 2: ≥140/≥90 Hypertensive Crisis: >180/>120

Etiology: is microbial root sampling reliable?

No (according to Sathorn's meta-analysis)

Etiology: What were Sundqvist's observations regarding bacteria in necrotic teeth with either a PARL or no PARL?

No microorganisms were found in any of the teeth without periapical destruction; and bacteria were found in almost all teeth with periapical destruction. As many as 12 different strains were found in one tooth, 88 different strains were identified in total (in 1976) 90% of the strains identified were anaerobic.

Application of Biologic Principles: Is the application of long-term CH advocated?

No, according to Blomlof, long-term CH use can cause PDL necrosis. According to Andreasen: Long-term CH use decreased dentin fracture resistance.

Application of Biologic Principles: are narcotics considered effective for patients with trigeminal neuralgia?

No.

Pathogenesis: Is the pulp ever involved in pressure resorption?

No. Additionally, some outside factor must be involved for pressure resorption to occur.

Medical History: Your patient has a history of Coronary Artery Bypass Graft (CABG) surgery, as well as a stent placed. Is an antibiotic prophylaxis necessary?

No. If the patient recently had these procedures done, a medical consult is indicated.

Treatment: You need to remove gutta percha from a canal to prepare for a post. Is the use of chloroform advisable?

No. It will result in the shrinkage of the gutta percha, leading to microleakage.

Radiographic Interpretation: Can x-ray photons deviate in their trajectory via magnetism?

Nope. But their trajectory can change via deflection from heavy metals or other dense objects.

Complications of Treatment: you have a traumatized tooth that tests non-vital. Do you treat it with a root canal?

Not necessarily. Bhaskar indicated that in traumatic cases the nerve supply can be damaged while the vascular supply remains intact. Therefore, a vital tooth can test non-vital. This is the basis for looking for two signs of pulp necrosis. Signs can include - no response to cold/EPT - discoloration - PARL - Sinus Tract - Abscess

Treatment: Do Posts strengthen roots?

Not usually. Schwartz and Robbins indicated that bonded posts can strengthen a root in at least the short-term.

Objective Examination: How does cold testing work with A-delta fibers?

Occording to Trowbridge, cold testing relies on the outward movement of hydrodynamic fluid to stimulate the A-delta fibers. Heat testing drives dentinal fluid towards the pulp, also stimulating the A-delta fibers. EPT creates ionic changes in the pulp, thus stimulating the nerve fibers (Bender).

Radiographic Interpretation: According to Slowey, how can you use a working length film to determine whether or not there is an extra canal?

Often, they will be seen as dark lines running parallel to the WL instrument in the coronal third of the root.

Pathogenesis: When does pressure resorption occur?

Pressure resorption occurs in response to direct damage to the precementum.

Treatment: According to Oesterle (1991), which treatment maintains a better crown:root ratio: orthodontic extrusion or surgical crown lengthening?

Orthodontic Extrusion

Diagnosis: What is a PAI Score?

PAI = PeriApical Index This was coined by Ørstavik in 1986, and based on the Brynolf'sradiographs. Purpose: Analysis and categorization of radiographic periapical lesions. *PAI 1* was assigned to normal apical periodontium; *PAI 2* referred to bone structural changes indicating, but not pathognomonic for, apical periodontitis; *PAI 3* was given to cases with bone structural changes with some mineral loss characteristic of apical periodontitis; *PAI 4* denoted a well defined radiolucency; *PAI 5* indicated a lucency with radiating expansion of bone structural changes.

Complications of Treatment: Describe POOR PASTAM. Crump (1979)

POOR PASTAM is an acronym to assess the possible reasons for endodontic failure, as described by Crump (1979). There are two categories: - Iatrogenic (POOR) - Non-Endodontic (PASTAM) *Perforation* - pain short of working length or persistent bleeding; angled radiographs can be useful. *Overfill* or inadequate *Obturation*- may suggest incomplete preparation or absence of a proper apical stop. *Root* or Root Canal missed- angled films or a presence of thermal sensitivity in a previously tx tooth. *Periodontal disease* - bone and attachment loss, probing, and thermal testing may help differentiate. Developmental grooves, narrow deep pockets, or adverse occlusal factors may be present. *Another tooth* - thermal testing, EPT, and evaluating other teeth for discoloration, percussion sensitivity, or mobility are key factors. *Split tooth* - vertical root fx are associated w/ narrow deep pockets and low grade chronic pain often relieved for a short period of time by occlusal adjustment. Transillumination and exploratory surgery can be used for diagnosis. *Trauma* - the diagnosis is confirmed only if elimination of the trauma results in permanent resolution of the radiographic and clinical signs and symptoms. *Anatomical variation (Senia)* *Microleakage-coronal*

Diagnosis: What is a hallmark symptom of malignancy?

Paresthesia. If paresthesia is present, then it's malignant until proven otherwise. This is also a good way to delineate between infection and malignancy.

Medical History: what patients are prone to stroke?

Patients with any or multiples of the following: 1. HTN 2. Congestive heart failure 3. Diabetes 4. Transient Ischemic Attacks (TIA) 5. Previous history of stroke 6. > 75yo

Treatment: You notice that a previously treated tooth has a short fill and poor taper, with no PARL. Do you retreat the tooth?

Perhaps, depending on the clinical significance of that tooth. According to *Bergenholtz (1979), 94% of previously treated teeth w/o PARL never developed a PARL after ReTx.* In his study of 660 previously treated teeth, 81% were able to obtain patency, even though 57% didn't have a radiographically visible canal.

Define: Periapical Abscess, Periapical Granuloma, Periapical True Cyst, and Periapical Pocket Cyst, according to Nair.

Periapical abscess - a focus of acute inflammation characterized by the presence of a distinct collection of PMNs within an already existing chronic granuloma. Periapical granuloma - a chronic inflammation that consists of a granulomatous tissue that is predominantly infiltrated with lymphocytes, plasma cells, and macrophages. These lesions may be epithelialized or non-epithelialized. Periapical true cyst - an apical inflammatory lesion with a distinct pathologic cavity completely enclosed in an epithelial lining so that no communication to the root canal exists. Periapical pocket cyst - an apical inflammatory lesion that contains a sac-like, epithelium-lined cavity that is open to and continuous with the root canal.

Etiology: What is the most likely non-endodontic source of orofacial infection? Why is this information relevant to your practice?

Periodontal disease, which can often mimmick a toothache (pain of PDL origin). According to Berman and Hartwell: Periodontal infections are not prone to present with diffuse facial swelling. Endodontic infections are more prone to facial swelling.

Diagnosis: Discuss Dentin Dysplasia Type I (Dentin Dysplasia)

Permanent and deciduous teeth are of normal shape, form, and consistency. Radiographically, the teeth have short roots, typically with sharp, conical apical constrictions. Pre-eruptive pulpal obliteration results in a crescent-shaped pulpal remnant parallel to the CEJ in permanent dentition and total pulpal obliteration in the deciduous dentition. Usually numerous periapical radiolucencies are present in non-carious teeth. The dentinal tubules are often blocked or shunted from their usual paths by numerous and sometimes massive true denticles. Shields 1973

Define: substantivity

Persistence of effect of a topically applied drug or cosmetic, determined by the degree of physical and chemical bonding to the surface; resistance to removal or inactivation by sweating, swimming, bathing, and friction, among other factors. In other words...its staying power. Does it stick around, or is it inactivated quickly? Chlorhexidine gluconate (CHX) mouthrinse has great substantivity, meaning it is retained in the oral cavity for extended periods of time and provides a slow and sustained release of the active ingredient.

Diagnosis: What is the most commonly reported symptom for multiple myeloma? What are the sites that are most commonly affected?

Persistent bone pain. Most commonly affected sites: 1. spine 2. ribs 3. sternum

Diagnosis: What is the difference between a pulp polyp and Pink Tooth of Mummery?

Pink Tooth of Mummery is an older term, and refers to a tooth with internal resorption.

Pathogenesis: According to Sundqvist (1989), What are the three primary bacteria suspected of being responsible for purulent inflammation?

Porphyromonas endodontalis Porphyromonas gingivalis Prevotella intermedia/Prevotella nigrescens (black pigmentation) These cells have the ability to invade, and can degrade Complement as wells as disrupt existing fibrin and the production of new fibrin (thus affecting the host's ability to form a clot). PMNs (neutrophils, leukocytes) are resisted, suggesting these organisms may be able to impair them.

Treatment: What are the pros and cons of maintaining apical patency?

Pros: - Improves apical irrigation efficiency - May decrease post-op pain Cons: - Causes transportation of the apical foramen - Increases the number of apical cracks

Who is the original authority on fatigue of NiTi files?

Pruett (1997)

Diagnosis: List the AAE accepted terminology for both pulpal and periapical diagnoses.

Pulpal Diagnosis: 1. Normal Pulp 2. Reversible Pulpitis 3. Asymptomatic Irreversible Pulpitis 4. Symptomatic Irreversible Pulpitis 5. Pulp Necrosis 6. Previously Initiated Therapy 7. Previously Treated Periapical Diagnosis: 1. Normal Apical Tissue 2. Asymptomatic Irreversible Pulpitis 3. Symptomatic Irreversible Pulpitis 4. Condensing Osteitis 5. Acute Apical Abscess 6. Chronic Apical Abscess

Pathogenesis: Humoral Response + Cellular Response = ?

Pulpal Inflammation.

Complications of treatment: what is the interaction of local anesthetics with a vital pulp, and why might this be a concern with direct and indirect restorative preparations?

Remember: Pashley and Kim A PDL injection may not be the best idea when doing a crown prep or cavity prep. Local anesthetics decrease pulpal blood flow, thus increasing the concentration of irritants permeating the dentin during a dental procedure, which can in turn cause necrosis.

Treatment: What is the treatment for a tooth with a necrotic pulp with an immature apex? What material do you use for apexification? What other materials have been used.

Revasculariztion to induce root end closure, dentinal canal width, and increase in root length. Can use h triple antibiotic paste (Hoshino's triple mix) or CaOH (Huang) after the canal has been irrigated with NaOCl, others to quote Trope, Hargreaves. CaOH: Cvek (1972), Tricalcium phosphate: Roberts and Brillant (found no better than MTA), Collagen calcium gel: Nevins (1976), Freeze dried bone, blood clots (Nygaard-Otsby 1950s)

Treatment: Who introduced ultrasonics to endodontics?

Richman (1957)

Complications of Treatment: What are the risks factors for a flare-up, and what is the effect of post-operative flare-ups on the prognosis of the RCT?

Risk Factors (Torabinejad): 1. Pre-op Pain 2. Pro-op analgesic use 3. Age (> 40yo) 4. Sex (Female) 5. Tooth Type (mandibular teeth) 6. ReTxs Effect on Prognosis: According to Friedman - none.

Treatment: What is the goal of endodontic access? What author do you credit?

Robinson, Goerig, Neaverth (1989) Endodontic Access: an update Goal: to obtain an unrestricted access to the apical 1/3 of the root.

Objective Examination: What is the EPT best at doing?

Ruling out pulpal necrosis. According to Jespersen, a positive response to EPT was accurate 90% of the time (ie. pulp was in fact, vital).

Application of Biologic Principles: What is a Schedule I drug?

Schedule 1 (I) drugs, substances, or chemicals are defined by the federal government as drugs with no currently accepted medical use and a high potential for abuse. Schedule 1 (I) drugs are the most dangerous drugs of all the drug schedules with potentially severe psychological or physical dependence. Examples: -Heroin -Lysergic acid diethylamide (LSD) -Marijuana (cannabis): controversial scheduling -Methylenedioxymethamphetamine (ecstasy) -Methaqualone -Peyote

Application of Biologic Principles: What is a Schedule II drug?

Schedule 2 (II) drugs, substances, or chemicals are defined as drugs with a high potential for abuse, less abuse potential than Schedule 1 (I) drugs, with use potentially leading to severe psychological or physical dependence. These drugs are also considered dangerous. Examples: -Cocaine -Methamphetamine -Methadone -Hydromorphone (Dilaudid) -Meperidine (Demerol) -Oxycodone (OxyContin) -Fentanyl -Dexedrine -Adderall -Ritalin

Application of Biologic Principles: What is a Schedule III drug?

Schedule 3 (III) drugs, substances, or chemicals are defined as drugs with a moderate to low potential for physical and psychological dependence. Schedule 3 (III) drugs abuse potential is less than Schedule 1 (I) and Schedule 2 (II) drugs but more than Schedule 4 (IV). Examples: -Combination products with less than 15 milligrams of hydrocodone per dosage unit (Vicodin) -Products containing less than 90 milligrams of codeine per dosage unit (Tylenol with codeine) -Ketamine -Anabolic steroids -Testosterone

Application of Biologic Principles: What is a Schedule IV drug?

Schedule 4 (IV) drugs, substances, or chemicals are defined as drugs with a low potential for abuse and low risk of dependence. Examples: -Xanax -Soma -Darvon -Darvocet -Valium -Ativan -Talwin -Ambien

Application of Biologic Principles: What is a Schedule V drug?

Schedule 5 (V) drugs, substances, or chemicals are defined as drugs with lower potential for abuse than Schedule 4 (IV) and consist of preparations containing limited quantities of certain narcotics. Schedule 5 (V) drugs are generally used for antidiarrheal, antitussive, and analgesic purposes. Examples: -Cough preparations with less than 200 milligrams of codeine or per 100 milliliters (Robitussin AC) -Lomotil -Motofen -Lyrica -Parepectolin​

Medical History: Your patient has had a history of Pseudomembranous Colitis, and they will require and antibiotic for treatment. What do you need to be cautious of?

Schedule appointments when the patient is free of disease. Don't prescribe Clindamycin Do not prescribe extended-duration antibiotics. Note: The elderly are particularly sensitive to colitis, use caution with antibiotics.

Treatment: What early (1974) name in endodontics is credited for the benchmark in cleaning and shaping the root canal system?

Schilder

Treatment: who was one of the first authors to expound on the importance of a 3D obturation?

Schilder (1967)

Treatment: a 3D adapted obturation is indicated for successful endodontics. Who was the first to indicate this?

Schilder in 1967.

Treatment: What is an Impedence-type apex locator?

Second generation apex locator (Endocater) operate on the principle that the tooth has differing electrical impedance across the walls of the root canal; the difference increase toward the apex. At the DCJ constriction, there is an abrupt drop-off in impedance that the apex locator detects.

Prognosis: What are the success rates for endodontic treatment of teeth with AP vs no AP?

Seltzer and Bender (1963): - No lesion 92% success - Lesion 76% success -Sjogren et al (1990): - No lesion: 96% success - Lesion: 86% - ReTx w/ Lesion: 62% Friedman (2003) Toronto Study Phase I: Clincal - No lesion: 92% - Lesion: 74% Friedman (2004) Meta-analysis: -No Lesion: 98% Success -Lesion: 86% Success

Pathogenesis: What is the big name to remember with barodontalgia?

Senia

Objective Examination: What's the difference between Sensitivity and Specificity?

Sensitivity: the probability that a test will identify a diseased tooth. Specificity: the probability that a test will identify the absence of disease.

Radiographic Interpretation: traditional film utilizes photosensitive silver halides to capture an image with x-radiation. What are the two silver halides used to accomplish this?

Silver bromide (primary) and silver iodide.

Complications of Treatment: You did the root canal, why isn't that lesion healing?

Sjogren and Sundqvist suggest the following reasons for a non-healing periapical lesion: 1. Endodontic treatment didn't eliminate all the bacteria from the canal. 2. Bacteria is persisting in areas that are inaccessible to RCT. 3. Actinomyces or Arachnia bacteria may persist in the periapical tissue. 4. Infected dentin chips may be forced out into the periapical tissue during mechanical instrumentation.

Radiographic Interpretation: What is the difference between "soft radiation" and "hard radiation"?

Soft radiation: - long wavelengths - decreased frequency - decreased energy - poor power of penetration - absorbed easily - readily ionized Hard radiation: - short wavelengths - increased frequency - high energy - strong ability to penetrate - does not get absorbed easily - does not ionize easily

Etiology: What is significant about "sterile necrosis."

Sterile necrosis is simply the death of the pulp tissue via loss of vascularity in the absence of bacteria. It is typically the result of trauma. A tooth with sterile necrosis is more susceptible to bacterial invasion, as it has no inherent defenses anymore. Therefore a root canal is encouraged.

Radiographic Interpretation: What is the primary compound found on traditional radiograph film, and who developed it?

Stuber, with the Eastman Kodak company, developed the first silver halide film specifically for use in dentistry.

Diagnosis: define: paroxysmal

Sudden and unpredicted; "out of nowhere." Paroxysmal pain is pathopneumonic for trigeminal neuralgia.

Root Canal Anatomy: Krasner & Rankow. 2004. Anatomy of the Pulp Chamber Floor. Discuss.

Summary: Clinical advise on correct location of canal orifices via observed Laws of Anatomy. Law of Centrality Law of Concentricity Law of the CEJ Law of Symmetry 1 Law of Symmetry 2 Law of Color Change Law of Orifice Location 1 Law of Orifice Location 2 Law of Orifice Location 3

Application of Biologic Principles: What is Super EBA?

Super EBA is a reinforced zinc oxide cement consisting of 32% Eugenol and 68% Ethoxy benzoic acid (EBA).

Etiology: Define Symbiosis, Commensal, Antibiosis, Amphibiosis

Symbiosis - The living together or close association of two dissimilar organisms. This represents a good relationship between the host and microorganisms. Commensal - The living together or close association with another organism and deriving benefit without injuring or benefiting the other individual. Antibiosis - An association between different organisms which is detrimental to one or both of them. Amphibiosis - An association between different organisms which can have both good and bad effects.

Treatment: What is TERM?

Temporary Endodontic Restorative Material. According to Hutter et al, Cavit provided a significantly better seal than TERM over a 3-week period.

Diagnosis: What is a pulp polyp?

The AAE defines it as: a form of chronic pulpal inflammation usually following carious or traumatic exposure in a young patient; characterized by a proliferation of dental pulp tissue from the exposed pulp chamber that fills the cavity with a pedunculated or sessile, pinkish-red, fleshy mass, usually covered with epithelium.

Treatment: Discuss The Law of the CEJ

The CEJ is the most consistent, repeatable landmark for locating the position of the pulp chamber. "Given the observation that the CEJ is the most reliable guide for access, we encourage the clinician to ignore the clinical crown as a guide in directing access, and instead, recommend the use of the CEJ as the ultimate "Northstar" for locating the pulp chamber." Krasner & Rankow

Etiology: What is the Focal Infection Theory, and is it valid?

The Focal Infection Theory asserts that localized or generalized infection can result frmo dissemination of bacteria and toxic byproducts from a focus of infection. This was advocated by Westin Price in 1925. Easlick refuted Price in 1952, pointing out the several fallacies of Price's studies, including: -inadequate use of controls -large amounts of bacteria in the cases presented -contamination of RCT teeth during extraction. Fish also refuted Price, and described how the both will attempt to encapsulate infections in so-called "Zones of Fish."

Application of Biologic Principles: What is the Hollow Tube Theory? Is it a valid theory?

The Hollow Tube Theory was developed by Rickert & Dixon in 1931. A hollow tube (for example, the space created between gutta percha that didn't reach the apex and the apex that has been hollowed out via instrumentation) provides a space where circulatory elements can seep and stagnate, leading to the release of toxins and the induction of inflammation. This theory was used to advocated for root canal fillings that extend to the radiographic apex. The theory was later disproved by Torneck in 1966 (35 years later), when he demonstrated that a canal that is thoroughly cleaned and debrided can heal in the presence of a short-fill, assuming the periapical tissues have a normal capacity for healing. Grahnen & Hansen (1961) demonstrated that more healing occured with a short fill than with a flush fill or long fill.

Complications of Treatment: What nerve tends to be permanently damaged when giving an IA with Septocaine?

The Lingual nerve

Treatment: What is another name for the Ochsenbein-Luebke Flap?

The Submarginal Flap.

Prognosis: Describe The Toronto Study. Friedman (2003)-The Toronto Study-Phase I (4-6 yr outcomes)

The Toronto Study was an epidemiological/meta-analysis study carried out by Friedman in 2003-2004. The study looked at success rates for endodontics over 4-6 years. Grad endo clinic- Overall success was 81%; w/o PARL was 92% and w/ PARL was 74%. (Strict criteria) Lesion decrease in size=success - overall was 92% and - functional was 97% success. Vital pulps was 95% and Non-vital pulps were 75%. Phase II study-no good due to 2 techniques used and multiple providers/instruments, very poor recall rate *The Meta-Analysis* No AP: initial RCT/retx were both 92%-98% disease free With AP: Intial RCT/retx: 74%-86% completely healed; 91%-97% functional (heal + healing) Apical surgery: 37%-85% complete healing (weighted avg 70%), 86%-92% functional (With modern surgical techniques, Rubinstein had success with SOM and EBA at 91.5% at 5-7 yrs)

Radiographic Interpretation: What is the difference between the anode and cathode?

The cathode is the negatively charged portion of the tubehead, the anode, typically made of tungsten, is the positive pole.

Treatment: Discuss the Law of Color Change

The color of the pulp-chamber floor is always darker than the walls. Krasner & Rankow. 2004

Biologic Principles: What is the Complement Cascade?

The complement system is a part of the immune system that enhances (complements) the ability of antibodies and phagocytic cells to clear microbes and damaged cells from an organism, promotes inflammation, and attacks the pathogen's cell membrane. It is part of the innate immune system, which is not adaptable and does not change over the course of an individual's lifetime. The complement system can be recruited and brought into action by antibodies generated by the adaptive immune system.

Radiographic Interpretation: How do you place the sensor and the tube head when taking an extra-oral radiograph of a mandibular posterior tooth?

The cone is positioned at a negative 35 angle to the occlusal plane.

Radiographic Interpretation: How do you place the sensor and the tube head when taking an extra-oral radiograph of a maxillary posterior tooth?

The cone is positioned at a negative 45° angle to the occlusal plane.

Radiographic Interpretation: What is the single most important determinant for FOV size in any imaging study?

The diagnostic task.

Radiographic Examination: If the mental foramen is visible on a PA, what angle is the radiograph likely to have been taken from?

The distal, according to Ace Goerig (1987)

Pathogenesis: Why can pulpal irritation occur years after dental treatment was rendered.

The effects of restorative dental treatment are considered to be cumulative over a lifetime. These cumulative effects that result in pulpal irritation is known as "Stressed Pulp Syndrome," as described by Abou-Rass.

Anatomy: what is the major artery that supplies blood to the facial structures?

The external carotid artery. One of the two branches of the external carotid artery is the Maxillary Artery, which supplies vascularity to the dentition. The Maxillary artery further divides into the Inferior Alveolar Artery (and Mental/Incisive arteries), which supplies blood to the mandibular teeth.

Treatment: Discuss the Law of Centrality

The floor of the pulp chamber is always located in the center of the tooth at the level of the CEJ. Krasner & Rankow. 2004

Radiographic Interpretation: What do amperes measure?

The height of a wave form.

Biologic Principles: how does inflammation lead to bone resorption?

The introduction of bacteria and their byproducts to the alveolus via either endodontic or periodontal infection leads to host immune and inflammatory responses. Pro-inflammatory mediators, including TNF-α, IL-1, PGE2, all promote osteoclastic activity, thus leading to bone resorption. Immune response cells (neutrophils, macrophages, lymphocytes) promote the upregulation of pro-inflammatory mediators as well as the activation of the RANK-L expression pathways.

Treatment: Discuss the Law of Orifice Location 1

The orifices of the root canals are always located at the junction of the walls and the floor. Krasner & Rankow. 2004

Treatment: Discuss the Law of Orifice Location 2

The orifices of the root canals are located at the angles in the floor-wall junction. Krasner & Rankow. 2004

Treatment: Discuss the Law of Symmetry 2

The orifices of the root canals are located at the angles in the floor-wall junction. Krasner & Rankow. 2004

Treatment: Discuss the Law of Orifice Location 3.

The orifices of the root canals are located at the terminus of the root developmental fusion lines. Krasner & Rankow. 2004

Treatment: Is chloroform safe to use in the dental operatory?

The permissible exposure limit to chloroform for an 8-hour period is 2.0ppm In 1992, *McDonald* and Vire conducted a study that found less than 0.57ppm for a 5.5 hour sample (well below permissible limits). This demonstrates that there is minimal (if any) health hazard to staff and patient.

Complications of Treatment: According to Iqbal, what is the single most important predictor of a flare-up during endondontic treatment?

The presence of a periapical lesion.

Radiographic Interpretation: how do the anatomic and radiographic mental foramen sizes differ?

The radiographic size of the foramen was smaller than the anatomic size (corresponding to the smallest diamter of the foramen on the internal surface of the buccal plate.

Prognosis: A patient asks: "What are the chances that retreating this tooth will succeed?" How do you respond?

The reasons for retreatment vary among patients, but generally involve either a PARL or a poorly obturated tooth, or both. Gorni and Gagliani give a 62%-90% success rate depending on whether or not a lesion is present. Ng did a meta-analysis, and demonstrated that Teeth with satisfactory root fillings had 41% higher success rates than those with poor fillings. The pooled success rate for teeth with satisfactory restorations was 24% higher than for those with poor restorations.

Treatment: You decide that you need an intra-osseous injection to anesthetize a mandibular molar. You successfully place your X-tip and are ready to deliver anesthesia. What type of anesthetic will you use, and why?

The studies out of Ohio St (Reader et al) have demonstrated that the conventional block was successful at achieving pulpal anesthesia 25% of the time. - the first IO with Mepivicaine elevated the success rate to 80% - the second IO with Mepivicaine elevated it to 98% Without a conventional IA block, 2% Lidocaine saw a 74% success rate, compared to 45% for Mepivicaine. After 20 minutes, 62% of the teeth in question still had pulpal anesthesia, whereas only 24% of the Mepivicaine group could claim the same. Reader also noted that the perforation of the cortical plate, and the deposition of anesthetic solution produced little/no pain, and healed quickly.

Etiology: What is the difference between Gram + and Gram - bacteria?

The term Gram +/- bacteria stems from classic microbiology laboratory detection techniques. A crystal violet dye was used, and the gram + bacteria would have an affinity to it. This is attributed to their thick peptidoglycan cell wall absorbing the color. Gram - bacteria have a cell wall that contains Lipopolysaccharide (LPS) - aka endotoxin - which does not readily accept the violet dye.

Radiographic Interpretation: what is a downside to using small file sizes to find a working length via radiographs?

The tips of small file sizes are not always visible radiographically.

Treatment: You have a patient who is coming in with an irreversible pulpitis. They cannot afford a root canal right now, but they really want to save the tooth. What treatment can you do to get them out of pain? How effective is this treatment?

The treatment of choice in this circumstance is an emergency pulpotomy. According to *Trope* (2004): Success rate of the pulpotomy treatment in regards to pain relief was 90% at 6 months and 78% at 12 months. So, this procedure will buy time for the patient, but no more than 12 months.

Treatment: Discuss the Law of Concentricity

The walls of the pulp chamber are concentric to the external surface of the tooth at the CEJ. Krasner & Rankow. 2004

Treatment: What is the The Hydrodynamic Theory?

Theorized by Brannstrom in 1972, it presents the idea that tooth pain is related to the rapid displacement of dentinal fluid.

Treatment: What is a Frequency-dependent Apex locator?

Third generation apex locator (Endex; Root ZX) operate on the principle that there is a maximum difference of impedance between electrodes depending on the frequencies used. A lip clip is used, and the unit is calibrated by the insertion of the file into the coronal portion of the canal. In this position, the difference in impedance value between the two frequencies is nearly constant. As the file is worked to length, the difference in impedance value begins to differ greatly; it is maximally different at the apical constriction, and the unit signals. Frequency-dependent apex locators use much less current than the resistance-type, reducing any sensation the patient feels in his/her lip. The unit can operate in an electroconductive environment and in the presence of pus and pulpal tissue; it may be overloaded, however, if the tooth is filled to the level of the pulp chamber. When retreating, all the existing gutta percha must be removed because it has insulating properties that may cause inaccurate readings.

Radiographic Examination: Describe "anatomical noise," from Seltzer and Bender

This study demonstrated that periapical lesions confined to cancellous bone cannot be seen because of the projection of overlying anatomy, hence "anatomical noise."

Diagnosis: Oehlers. 1957. Dens invaginatus (Dilated composite odontome) I. Variations of the invagination process and associated anterior crown forms.

Three Types of Invaginations, and three anterior crown formations. Types 1-3 and Groups 1-3, respectively.

Medical History: Your patient presents with hyperthyroidism. What would be your chief concern for them?

Thyroid Storm (i.e. Thyrotoxic Crisis). It is characterized by dangerously sharp increases in heart rate, blood pressure, and body temperature. This can be precipitated by the following: 1. Infection 2. Trauma 3. Surgical Procedures 4. Stress Patients with incompletely treated or untreated thyrotoxicosis are senistive to epi, so avoid use until the condition becomes well-managed. Signs of early stage thyrotoxicosis: 1. severe symptoms of thyrotoxicosis (HR, BP) 2. Fever 3. Abdominal Pain 4. Delirious, obtunded, psychotic

Medical History: What is the purpose of insulin?

To allow tissues to intake glucose (with the exception of the brain and nervous tissue. They do not require insulin for this purpose).

Prognosis: According to Bender (1966), what must you consider to assess endodontic success, and what is the criteria for success?

To assess endodontic success, clinical, radiographic, and histological findings must be considered. Criteria for success: 1. Absence of pain or swelling 2. Disappearance of fistula 3. No loss of function 4. No evidence of tissue destruction 5. Radiographic evidence of eliminated or arrested area of rarefaction after post-tx interval of 6 mo to 2 yrs

Complications of Treatment: What is difference between cyclic and torsional fatigue? Which instruments are affected?

Torsional fatigue: breaking of instrument by binding at the tip (smaller instruments) Cyclic fatigue: breaking by excessive bending back and forth (larger instruments)—Pruett (1997)

Treatment: what is the best irrigant to use for root canals?

Trick Question, there is no single irrigant that is considered the best. *Yamada* (1983) recommends the combination of irrigants to best clean and disinfect a root canal system. NaOCl is always recommended as the final irrigation solution. According to *Calt & Serper*: Using EDTA first, then NaOCl as the final rinse, you are able to completely remove calcium hydroxide from a canal, which allows the sealer to better penetrate tubules.

Pathogenesis: How fast can LPS (endotoxin) travel to the canal system of an endodontically treated tooth with a poor restoration?

Trope indicates as early as 18 days. Alves showed it can happen as early as 8 days, or in roughly 1/3 the time it would take for the bacteria proper to get there.

Medical History: T/F Patients on hemodialysis are susceptible to hyperparathyroidism.

True

Pathogenesis: T/F: External Inflammatory Root Resorption is generally endodontic or orthodontic in nature.

True, per Tronstad.

Diagnosis: True/False: Invasive Cervical Root Resorption is typically asymptomatic, and are diagnosed incidentally via routine radiographs

True.

Radiographic Interpretation: What are the three primary materials used for a radiographic anode?

Tungsten (most popular), Silver, Molybdenum.

What are the Two types of immunological reactions, according to Torabinejad?

Type I (Humoral): - Ag-Ab complex reactions (local vascular inflammation) - Complexes fix complement, attract PMNS. - PMNS degranulate and release lysosomal enzymes, which induce tissue injury. - IgE-mediated reactions (anaphylactic) - antigen bridges to IgE molecules on mast cells, causing release of histamine. - Both pathways can induce bone resorption Type II (Cellular or Delayed Hypersensitivity) - Do not require the presence of an antibody - Sensitized T-lymphocytes + specific antigen = lymphocyte proliferation and lymphokine production (including osteoclast-activating factor). This leads to bone-resorption. - once activated, you can't shut down delayed hypersensitivity rxns until the antigen is completely removed.

Vertucci Classifications

Type I Single canal from chamber to apex Type II Two separate canals leave chamber & join to form 1 Type III Single canal leaves chamber, splits to 2, then joins to form 1 at apex Type IV Two canals from chamber to apex Type V Single canal leaves chamber then splits to exit as separate foramen Type VI Two canals leave chamber, merge, then split Type VII. Single canal leaves chamber, divides then rejoins within the body of the root, and then redivides into 2 distinct canals at apex Type VIII Three canals from chamber to apex

Weine Classification

Type I Single canal from chamber to apex Type II 2 separate canals leave chamber & join to form 1 Type III 2 separate canals from chamber to apex Type IV 1 canal leaves chamber and divides into 2

Treatment: what is the difference between ultrasonic and sonic?

Ultrasonic: 20,000+ Hz Sonic: 1500-8000 Hz

Application of Biologic Principles: You have a patient with a documented, severe allergy sulfa drugs and any sulfite preservatives. They need a root canal. What kind of anesthetic will you utilize?

Use an anesthetic that does not contain epinephrine, as they contain sulfite preservatives.

Application of Biologic Principles: According to Goldstein (1978), what are the two primary ways in which antibiotics utilized in endodontics effect bacteria?

Via disruption of cell wall synthesis or disruption of protein synthesis (affecting the bacteria's 30S or 50S ribosomal subunits).

Medical History: Hemophilia A and Von Willebrand's Dz both involve Factor VIII deficiency. What's the difference between the two?

Von Willebrand's Dz involves abnormal platelet adhesion.

Treatment: Who invented NiTi instruments?

Walia.

Complications of Treatment: What is the role of antibiotics in endondontic flare-ups?

Walton & Chiappinelli demonstrated a lack of any relationship with prophylactic Abx use and the incidence of flare-up or reduction of post-treatment symptoms. Reader confirmed Walton's findings on Abx prophylaxis, and also found that post-treatment Abx did not significantly reduce pain.

Prognosis: According to Sundqvist, what are the success rates for endodontically retreated cases when e. faecalis is discovered, and when no detectable microorganisms are discovered?

When E. Faecalis is present: 74% healed Without detectable microorganisms: 80% When obturated with recoverable microorganisms at the time of filling: 33% healed.

Radiographic Interpretation: What are low-energy photons (with regards to dental radiology), why are they bad, and how are they prevented from reaching the patient?

When voltage and heat are added to the radiographic cathode, a high volume of electrons are produced and directed at the anode. However, the electrons are not traveling at a uniform speed, therefore the photons that are produced upon collision with the anode will not have the same energy. Photons with lower energy have a softer radiation, meaning they are more readily absorbed by soft tissue. This soft tissue absorption adds to the total dose of radiation received by the patient, without giving any diagnostic value. Therefore, a filter (aluminum) is placed in the cone to absorb low-energy photons.

Objective Examination: when should a patient's temperature get measured?

When you suspect an infection.

Prognosis: According to Gorni and Gagliani (2004), what is the success rate for endodontically retreated cases with a lesion and without a lesion?

Without a lesion: 89.5% With a lesion: 61.7% *Of note: in cases where the canal morphology was respected during retreatment, the presence or absence of a periapical lesion did not significantly affect the prognosis.* *A retreatment case with a lesion AND altered morphology did not fair well at all.*

Radiographic Spectrum: How do x-rays differ from normal light waves?

X-radiation has shorter wavelengths/higher frequency. It is a "harder" radiation when compared with light waves, therefore it will contain more energy, be less likely to ionize, will penetrate soft and hard tissue more readily, and will not be easily absorbed. Practicality: we cannot use visible light radiation to take intra-oral images of teeth, as the light would be readily absorbed by the soft tissue. X-radiation is not absorbed significantly by soft tissue, and marginally by hard tissue (bone and tooth apparatus). This marginal changes are then picked up by the sensor, which contains a shield that prevents further penetration of the ray. In traditional film exposure, this would be the lead plate contained in the film packaging. The reason we are concerned about these Hard Radiation waves: their high energy and penetrating abilities can alter human tissue by ionizing cells, which then can increase the risk of developing mutant/cancerous tissue.

Complications of Treatment: Is it worth it to biopsy non-healing periapical lesions, since most of them are just granulomas and/or cysts.

YES!!!! Koivisto demonstrated that while 73% of non-healing lesions are granulomas or cysts, 20% were something different and had more severe pathological implications. So...it's worth it.

Pathogenesis: Are epithelial cells found in granulomas?

Yes! The main difference between granulomas and cysts however, is that cysts have organized epithelial cells, whereas granulomas do not.

Treatment: Do you use an electronic apex locator? When? Describe the accuracy of these devices.

Yes, I use it in all cases to determine if I've achieved patency. If patency is achieved, I use it to aide in determining a proper working length. - *Shabahang* 1996: need to establish patency to get a reliable reading from the Root ZX; *96%* accuracy. - Welk, Baumgartner, Marshall 2003: Root ZX accurately located the minor diameter 91% of the time - Wilson 2006: EALs and EPT do not interfere with cardiac pacemakers. - *Garofalo, Dor, Kuttler* 2002: EALs do not interfere with cardiac pacemakers The Root ZX uses the ratio of 2 different impedences to determine the minor constriction.

Complications of Treatment: Does suture removal run the risk of developing a bacteremia?

Yes, albeit low (5%) according to King. Giglio indicates that removing 5+ sutures increases the risk significantly, therefore Abx prophylaxis may be indicated for high risk (endocarditis) patients.

Complications of Treatment: According to Mente, can MTA successfully repair an iatrogenic perforation?

Yes.

Prognosis: can probing depths be an indicator of successful outcomes for surgical endodontics?

Yes. According to Lui, probing depths less than 3mm were associated with more favorable outcomes.

Radiographic Interpretation: How do you alter your exposure time when taking an extra-oral radiograph?

You double the exposure time.

Complications of Treatment: What happens when you combine liquid CHX and liquid NaOCl?

You get a solid Parachloroanaline, which is a carcinogenic.

Radiographic Examination: With regards to finding an extra canal, what would you be looking for on a working length radiograph?

You would look for any dark lines running parallel to the WL instrument in the coronal third of the root. (Slowey 1974)

Pathogenesis: According to Seltzer and Bender (1963), what is the correlation between diagnostic data for pulpal inflammation (clinical findings) and actual histologic findings in the dental pulp?

Your clinical findings will not always line up with the histological findings. Some important histologic/clinical findings: - Inflammation starts out as a low-grade and chronic, and can last for years before an acute response occurs -The prognosis for capping an exposed, chronically inflamed pulp is poor. -mechanical exposures often do not produce total pulpitis, therefore healing is often very good in the absence of prior inflammation and infection. -a previous history of pain is an important diagnostic sign of inflammation. -severity of pain is partially-related to the severity of inflammation. -pain upon percussion is indicative of inflammation associated with the PDL from either the pulp or periodontium sources.

Diagnosis: Discuss Dentinogenesis Imperfecta Type I

amber translucency of both deciduous and permanent dentition. Enamel often chips away, allowing speedy attrition of the remaining softer dentine. Radiographically, the deciduous and earlier permanent teeth show short, constricted roots, marked dentin hypertrophy, and accelerated pulpal obliteration. True denticles are also seen. Type I will always be observed with osteogenesis imperfecta, but a person can have osteogenesis imperfecta without showing dentinogenesis imperfecta. Shields 1973

Diagnosis: Discuss Dentin Dysplasia Type II (Anomalous Dysplasia of Dentin)

amber, translucent coloration in the deciduous dentition with obliteration of pulp chamber. Coloration is normal in the permanent dentition and a circumpulpal dentin hypertrophy produces a thistle-tube like pulp configuration with ubiquitous pulp stones. Shields 1973

Define: Paresthesia

an abnormal sensation, typically tingling or pricking ("pins and needles"), caused chiefly by pressure on or damage to peripheral nerves.

Treatment: According to DeCleen, what aspects of anatomy must be considered when placing a post?

curvatures, concavities, grooves, anomalies.

Define: Anesthesia

insensitivity to pain, especially as artificially induced by the administration of gases or the injection of drugs before surgical operations.

Diagnosis: Discuss Dentinogenesis Imperfecta Type III (Bradywine isolate hereditary opalescent destine)

multiple pulp exposures often observed in deciduous teeth. Considerable variation is seen radiographically even within the same individual. Shields 1973

Diagnosis: Discuss Dentinogenesis Imperfecta Type II (Hereditary Opalescent Dentine)

similar to type I except families that demonstrate dentinogenesis imperfecta type II never have osteogenesis imperfecta. Also in this type, both dentitions are equally affected and normal teeth are never seen. Shields 1973

Define: Analgesia

the inability to feel pain.

Radiographic Examination: What are the four main categories for describing a radiograph?

— Localization — Periphery and Shape — Internal Structure — Effects on Surrounding Structures White and Pharoah In other words: — Is the lesion localized to one area of the jaw, or is it more generalized? — Are the borders of the lesion ill-defined or well-defined? Do they have a consistent shape or an irregular shape? Scalloped borders? Corticated or sclerotic borders? — Is the internal structure radiolucent, radiopaque, or mixed? — Is the lesion doing anything to the surrounding tooth/teeth, lamina dura? Is there displacement, widening, resorption?

Radiographic Examination: How are CBCTs different from Traditional CTs?

—CBCT images are captured from a cone-beam, whereas traditional CTs have a fan-shaped beam. —CBCT requires only one rotation to capture its images, and can therefore get the information in less time and less radiation. —CBCT can be done with the patient seated upright


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