RD 2 Midterm Questions
Non-working side interferences generally occur on the inner aspect of which teeth? 1. facial cusps of mandibular molars 2. facial cusps of maxillary premolars 3. lingual cusps of maxillary molars 4. facial cusps of maxillary molars A. 2 and 4 B. 1 and 3 C. 2 and 3 D. 3 and 4
B. 1 and 3
ZOE can be both toxic and therapeutic. Explain why ZOE placed directly on tissue has a toxic effect rather than a therapeutic effect.
-Eugenol in ZOE is toxic to the pulp in high concentrations
After placing the Tofflemire matrix band for restoration of a Class 2 preparation, the operator should test with an explorer in a press-scrape motion along the gingival cavosurface margin. What is the purpose of this procedure? (Give at least 2 reasons)
-To check for gaps, trapped dam or tissue, and loose friable enamel (can also check to see if left any decay)
If the distal cusp of the mandibular first molar requires capping, what is the minimal thickness of amalgam necessary for capping this cusp? (the cusp is in occlusion prior to preparation)
2 mm
**Disadvantages of using Jet acrylic for direct fabrication of provisionals include 1. brittleness 2. high exothermic heat increase 3. poor polishability 4. toxic effect of free monomer 5. high volumetric shrinkage A. 2, 4 and 5 B. 1, 2 and 5 C. 2, 3, 4 and 5 D. 3, 4 and 5 E. 1, 2, 4 and 5
A. 2, 4 and 5 2. high exothermic heat increase 4. toxic effect of free monomer 5. high volumetric shrinkage
A 90 degree angle is the angle that 1. enamel prisms make with the outer surface of the tooth 2. dentinal tubules make with the DEJ 3. an amalgam restoration should make with the cavity wall at the cavosurface margin of the cavity preparation A. All of the above B. One of the above C. Two of the above
A. All of the above
***When viewing a class II amalgam cavity preparation from the proximal, which line angle is longest? A. Axiogingival B. Axiopulpal C. Both line angles are equal
A. Axiogingival
**A chamfer margin is formed as the negative image of a round-end tapered diamond; therefore a chamfer should not be wider than half the diameter of the bur used, otherwise a lip of unsupported enamel results. A. Both statements are true. B. Both statements are false. C. Statement one is true; statement two is false D. Statement one is false; statement two is true
A. Both statements are true.
Bond strengths in superficial dentin close to the detinoenamel junctions are greater than those for deep dentin because in deep dentin the greater number of tubules and the larger diameter of tubules reduce the amount of intertubular dentin available for bonding. A. Both statements are true. B. Both statements are false. C. Statement one is true; statement two is false D. Statement one is false; statement two is true
A. Both statements are true.
Cusp reduction (cusp capping) significantly decreases retention form of an amalgam preparation because of loss of height of the vertical walls. When additional retention is indicated, slots and grooves can be placed slightly pulpally from the dentinoenamel junction providing secondary retention. A. Both statements are true. B. Both statements are false. C. Statement one is true; statement two is false D. Statement one is false; statement two is true
A. Both statements are true.
Diamond burs are superior to carbide burs for the removal of dental enamel. Therefore, diamond burs are better for extra-coronal activity preparations, beveling enamel margins on cavity preparations, and enameloplasty. A. Both statements are true. B. Both statements are false. C. Statement one is true; statement two is false D. Statement one is false; statement two is true
A. Both statements are true.
In normal healthy circumstances, the oral flora capable of colonizing the teeth is not capable of causing disease. However, an active carious lesion can serve as a reservoir of Mutans Streptococci and lactobacilli, providing large threshold dose necessary to establish infections on other tooth surfaces. A. Both statements are true. B. Both statements are false. C. Statement one is true; statement two is false D. Statement one is false; statement two is true
A. Both statements are true.
The "wet bonding" technique has been shown to enhance bond strengths because water preserves the porosity of collagen networks available for monomer interdiffusion. If the dentin surface is dried with air, the collagen undergoes immediate collapse and prevents resin monomers from penetrating. A. Both statements are true. B. Both statements are false. C. Statement one is true; statement two is false D. Statement one is false; statement two is true
A. Both statements are true.
A dentist is preparing Tooth #30 for an occlusal amalgam restoration. Once the ideal outline form and depth have been established, the dentist notes that caries remains on the facial, pulpal, and lingual walls of the preparation. The next step in treatment is to A. Extend the outline form B. Remove the caries with a spoon excavator C. Remove the caries with a larger round bur on high speed D. Remove the caries with a large round bur on slow speed
A. Extend the outline form
***In a completed Class III cavity preparation for composite which of the following walls should remain in contact with the adjacent tooth? A. Incisal B. Gingival C. Facial D. Lingual E. all walls should break contact with the adjacent tooth
A. Incisal
Flowable resin composites generally have a ..... percentage filler content than other types of resin composites. A. Lower B. Higher
A. Lower
Initial pulpal inflammation is thought to be evident clinically by production of sharp pains. A short, painful response to cold with each pain lingering only a few seconds (<10 seconds) in response to the thermal stimulus is suggestive of A. Reversible pulpitis B. Irreversible pulpitis C. Necrotic Pulp
A. Reversible pulpitis
**Which of the following are true regarding caries originating on the root surface? 1. it has a comparatively rapid progression. 2. it is often asymptomatic 3. it is more difficult to restore 4. it is closer to the pulp than pit and fissure caries A. all of the above B. all of the above except one C. all of the above except two
A. all of the above
**Which of the following statements regarding quadrant dentistry is/are true 1. it is recommended to restore the most posterior tooth first 2. if proximal boxes differ in size, teeth with smaller boxes should be restored first 3. when restoring a quadrant of Class II amalgam tooth preparations, it is permissible to apply matrix bands on alternate preparations in the quadrant and restore the teeth two at a time 4. using a finishing strip between newly placed contacting amalgam restorations may lighten or eliminate the proximal contact A. all of the above are true B. 1 and 2 C. 2, 3, and 4 D. 3, 4 E. 4
A. all of the above are true
The height of contour on the facial surface of posterior teeth is located A. in the gingival one-third of the tooth B. in the middle one-third of the tooth C. at the junction of the middle one-third and the gingival one-third D. at the junction of the middle one-third and the occlusal one-third E. It varies depending on the height of the tooth.
A. in the gingival one-third of the tooth
Microfill resin composites generally have a ... percentage filler content than other types of resin composites A. lower B. higher
A. lower
The words "overcarved" and "undercarved", "overcontoured" and "undercontoured" are used frequently by your laboratory instructors. If a surface is undercarved, the surface is also A. overcontoured B. undercontoured C. also undercarved D. none of the above
A. overcontoured
Non-working side interferences generally occur on the inner aspect of which teeth? 1. facial cusps of mandibular molars 2. facial cusps of maxillary premolars 3. lingual cusps of maxillary molars 4. facial cusps of maxillary molars A. 2 and 4 B. 1 and 3 C. 2 and 3 D. 3 and 4
B. 1 and 3 1. facial cusps of mandibular molars 3. lingual cusps of maxillary molars
Before inserting amalgam into an MOD cavity preparation, a matrix is placed around the tooth. Which of the following procedures should be accomplished next? 1. The band should be burnished into contact with the adjacent tooth. 2. The matrix retainer should be tightened as much as possible and reinforced facially and lingually with compound. 3. Tapered wedges should be placed interproximally to obtain close adaptation of the matrix at the gingival margins. 4. Tapered wedges should be placed carefully to hold the band in close adaptation to the gingival margin without separating the teeth. A. 1, 2, 3 B. 1, 3 C. 1, 3, 4 D. 1, 4 E. 2, 3
B. 1, 3
When placing a base on the pulpal floor, it is important to cover the entire floor of the preparation with the base; because it is better to have a base rather than dentin bear the compressive load of mastication. A. Both statements are true. B. Both statements are false. C. Statement one is true; statement two is false D. Statement one is false; statement two is true
B. Both statements are false.
A patient presents with an amalgam restoration fractured at the isthmus six months after placement. The most likely cause is A. Recurrent Caries B. Inadequate depth of the preparation C. Excessive width of the preparation D. Occlusally divergent lateral walls
B. Inadequate depth of the preparation
The current consensus is that dentin bonding agents bond primarily .... to tooth structure. A. Chemically B. Mechanically C. Via hydrogen bonding
B. Mechanically
?? A favorable prognosis for the pulp after direct pulp capping may be expected if which of the following criteria are met: 1. The exposure is small (< 1 mm in diameter) 2. Tooth sensitivity to a cold stimulus lasts longer than 10 seconds after stimulus removal. 3. The invasion of the pulp was traumatic with moderate physical irritation to the pulp. 4. Preparation was not prepared under the rubber dam 5. There is excessive hemorrhage from the exposure site A. All of the above B. None of the Above C. Two of the above D. Three of the above
B. None of the Above (exposure needs to be less than 0.5 mm)
Fracture of a complete cusp in posterior teeth is a common occurrence. In general, in all posterior teeth, the most frequently fractured cusps are the .... A. Supporting B. Nonsupporting C. All cusps fracture with equal frequency
B. Nonsupporting
Which one of the following materials is described as being sedative to a painful tooth? A. Calcium Hydroxide B. Zinc Oxide and Eugenol C. Glass Ionomer Cement D. Zinc Phosphate Cement
B. Zinc Oxide and Eugenol
Streptococcus mutans is considered to be a principle etiologic agent of caries because is produces organic acids and it A. metabolizes substrate from saliva B. forms a gelatinous matrix C. derives energy from enamel constituents D. lives symbiotically with Lactobacillus acidophilus
B. forms a gelatinous matrix
When a deep carious lesion occurs and there are no clinical or radiographic indications of irreversible pulp damage, the tooth may be treated by a procedure termed ..... This procedure involved the removal of infected dentin except for the deepest, last small amount, which if removed might expose the pulp. A. direct pulp cap B. indirect pulp cap C. preventive resin restoration D. sealant
B. indirect pulp cap
The most deleterious effect of polymerization shrinkage of composite resin is: A. increased wear B. microgap formation C. decreased stiffness D. increase in softness
B. microgap formation
When applying a Tofflemire matrix band to a tooth with a Class II preparation, the edge of the band with the larger circumference is always oriented ... and the open end of the U-shaped retainer is always oriented ... A. occlusally, occlusally B. occlusally, gingivally C. gingivally, gingivally D. gingivally, occlusally
B. occlusally, gingivally
The direction of retention pin holes should be A. parallel to the long axis of the tooth B. parallel to the nearest external surface C. perpendicular to the occlusal or the gingival floor of the preparation D. at right angles to the dentinal tubules E. at a 14 degree angle to the long axis of the tooth
B. parallel to the nearest external surface
The self polymerizing resin used in the preclinical laboratory (Jet) is a A. poly(ethyl methacrylate) B. poly(methyl methacrylate) C. poly(vinylethyl methacrylate) D. bis-acrylate
B. poly(methyl methacrylate)
**Gavelis et al found that tooth preparations with ..... permitted the most complete seating of a crown. A. parallel bevels B. shoulders C. chamfers D. reverse bevels
B. shoulders
The words "overcarved" and "undercarved", "overcontoured" and "undercontoured" are used frequently by your laboratory instructors. If a surface is overcarved, the surface is left A. overcontoured B. undercontoured C. also undercarved D. none of the above
B. undercontoured
The linear coefficient of thermal expansion of currently used composites is approximately ..... times that of tooth structure. *** A. 1.5 X B. 2.0 X C. 2.5 X D. 3.0 X E. 3.5 X
D. 3.0 X
According to the material presented in the Shillingburg text, a taper or total convergence of ... degrees has been proposed as being achievable clinically while still affording adequate retention. A. 9 B. 12 C. 16 D. 20 E. 25
C. 16
**Overcontoured crowns can be the result of 1. the need for added retention 2. overbulking by technicians 3. insufficient tooth reduction 4. periodontal considerations 5. lack of a functional cusp bevel A. all of the above B. 2, 3 and 4 C. 2, 3 and 5 D. 1, 3, and 5 E. 3 and 5
C. 2, 3 and 5 2. overbulking by technicians 3. insufficient tooth reduction 5. lack of a functional cusp bevel
??? According to the material presented in lecture, after performing an indirect pulp cap the operator will reenter the tooth after .... to continue caries excavation. This differs from the step-wise excavation technique which recommends reentering the tooth after .... to continue caries excavation. A. 4 weeks; 6-12 weeks B. 6-8 weeks; 4 months C. 6-8 weeks; 6-12 months D. 8-12 weeks; 12-16 months
C. 6-8 weeks; 6-12 months BOBERICK'S LECTURE + QUIZ SAYS 3-12 months for stepwise and indirect can be a final restoration
Which of the following clinical situations involving direct pulp capping would be the most likely to be successful? A. A pin-point exposure having sound dentin on the periphery of the exposure, with a mild degree of pulpal inflammation restricted to the exposure site. Poor isolation using cotton roles. B. A carious exposure having decayed or infected dentin at its periphery, inflammation in the pulpal tissues beyond the exposure site. Isolation using rubber dam. C. A pin-point exposure having sound dentin on the periphery of the exposure, with no pulpal inflammation at the exposure site. Isolation using rubber dam. D. An exposure with profuse hemorrhage and great involvement (mechanical) of the pulpal and root tissues
C. A pin-point exposure having sound dentin on the periphery of the exposure, with no pulpal inflammation at the exposure site. Isolation using rubber dam.
Wedge-wedging is best used in which of the following conditions? A. In patients with recession of interproximal tissue B. With faciolingually wide proximal boxes to provide maximum closure of the ban along the ginigival margin C. On the mesial aspect of maxillary first premolars to adapt the matrix band to the fluted (concave) area of the gingival margin
C. On the mesial aspect of maxillary first premolars to adapt the matrix band to the fluted (concave) area of the gingival margin
**Force applied to the occlusal surface of a crown at an oblique angle can produce a ling of action that passes outside the supporting tooth structure. The point on the margin closest to the line of action is the fulcrum point of center of rotation. If a line is drawn from the center of rotation perpendicular to the cement film of the opposite wall of the prep, the point where this line intercepts the cement film is called the tangent point. Apical to the tangent point of a crown preparation the forces have a component of ..... A. Compression B. Shear C. Tension
C. Tension -> apical (Compression -> incisal/occlusal, shear -> tangent)
**Which of the following is a true characteristic of the chamfer margin preparation? A. The chamfer design has shown experimentally to exhibit the most stress along the finish line. B. The chamfer has an acute edge at the finish line to allow for accurate seating of the restoration. C. The chamfer has sufficient depth at the margins to provide for an adequate thickness of gold. D. The chamfer offers an effective "slip joint" margin.
C. The chamfer has sufficient depth at the margins to provide for an adequate thickness of gold.
True or False: The pH of hard-set calcium hydroxide is about 7 (neutral).
FALSE
**In diagnosing Class 2 interproximal carious lesions that cannot be explored directly, a good supplement to the radiograph is A. reviewing the patient's history of caries activity B. examining the corresponding tooth in the occluding quadrant C. examining for color changes or loss of translucency beneath marginal ridges D. preparing the adjacent occlusal surface and examining the exposed proximal dentinoenamel junction
C. examining for color changes or loss of translucency beneath marginal ridges
Clinical interpretation of pain from pulpal inflammation (hyperemia) is somewhat empiric, but nonetheless important to the successful practice of operative dentistry. If an irritant , such as touching ice to the tooth, causes pain that lingers more than 15 seconds after removal of the irritant, the condition of the pulp is called ... and the resolution of the condition is possible by ... A. reversible pulpitis; root canal therapy B. reversible pulpitis; immediate restorative treatment (operative dentistry) C. irreversible pulpitis; root canal therapy D. irreversible pulpitis, immediate restorative treatment (operative dentistry)
C. irreversible pulpitis; root canal therapy
The copal resin varnish that is placed in the cavity preparation before the amalgam is condensed provides A. sealing of the margins for the lifetime of the restoration. B. long-term sealing of several years duration. C. short-term sealing of the margins. D. no sealing of the margins.
C. short-term sealing of the margins.
The term ..... refers to an operative procedure in which multiple teeth with acute threatening caries are treated quickly by (1) removing the infected tooth structure, (2) medicating the teeth, and (3) restoring the defects with a temporary material
Caries Control
***Which of the following statements is true concerning the use of bevels in Class III composite resin preparations? 1. Bevels improve bonding strength by increasing the surface area available for bonding. 2. Bevels provide for improved esthetics by allowing for a gradual blending of tooth and composite. 3. Bevels can vary in length depending on the need for retention. 4. Bevels can be placed using round or flame shaped diamond burs. 5. Bevels improve marginal seal and decrease microleakage and are equally effective above and below the CEJ. A. all of the above B. 1, 2, 4, and 5 C. 1, 2, and 3 D. 1, 2, 3, and 4
D. 1, 2, 3, and 4
**Which of the following statements is true concerning the preparation for a composite veneer 1. Mesial and distal contact should be broken for improved esthetics 2. The preparation should penetrate 1/2 the thickness of the enamel 3. The margin should always extend subgingival 4. Reduce the incisal edge to minimize the occurrence of protrusive interferences 5. The desired margin configuration is the chamfer A. All of the above B. 1, 2, 5 C. 2, 4, 5 D. 2, 5 E. 4, 5
D. 2, 5 2. The preparation should penetrate 1/2 the thickness of the enamel 5. The desired margin configuration is the chamfer
According to the material presented in the Shillingburg text, to minimize stress in the cement interface before the preparation and the restoration, an axial wall taper of .... degrees has been suggested as optimum; however research by Mack estimates that a minimum taper of .... degrees is necessary to insure the absence of undercuts. A. 2-6; 18 B. 3-5; 15-20 C. 6, 8 D. 2-6; 12
D. 2-6; 12
According to material presented in the Sturdevant text (p 813), when caries is extensive, reduction of one or more of the cusps for capping may be indicated. Complex amalgam restorations with one of more capped cusps have documented longevity of .... A. 44% after 5 years B. 50% after 9 years C. 62% after 12 years D. 72% after 15 years
D. 72% after 15 years
**The best method for accurate diagnosis of interproximal caries (Class II and Class III) is A. Reviewing the patient's history of caries activity B. Examining the corresponding tooth in the occluding quadrant C. Examining for color changes or loss of translucency beneath marginal ridges D. Radiographic Examination E. Probing with an explorer
D. Radiographic Examination
After the dentist has completed an etching procedure on a Class III composite preparation, the preparation becomes contaminated with saliva. In response, the dentist should do which of the following? A. Blow away the saliva with air, then proceed B. Rinse away the saliva with water, dry the preparation, then proceed C. Wipe away the saliva with a cotton pellet, rinse the preparation with water, dry it with air, then proceed D. Rinse away the saliva with water, dry the preparation with air, then repeat the etching procedure
D. Rinse away the saliva with water, dry the preparation with air, then repeat the etching procedure
True or False: Using only air as a coolant during cavity preparation does not cause pulpal damage because the dentinal tubules are effectively sealed by reparative dentin during rapid progression of the carious lesion.
FALSE
Using pins to retain amalgam restorations increases the risk of 1. Cracks in the teeth 2. Thermal sensitivity 3. Pulpal exposures 4. Periodontal ligament invasion A. 1 and 2 B. 3 and 4 C. 1, 3 and 4 D. all of the above
D. all of the above
According to the material presented in the Sturdevent text (p.859), remaining old restorative material on the internal walls of a preparation should be removed if which of the following condition(s) is (are) present: 1. The old material is judged to be thin, non-retentive or both. 2. There is evidence of caries under the material (radiographic and/or visual) 3. The pulp was asymptomatic preoperatively 4. The periphery of the remaining restorative material is intact A. all of the above B. none of the above C. one of the above D. two of the above E. three of the above
D. two of the above 1. The old material is judged to be thin, non-retentive or both. 2. There is evidence of caries under the material (radiographic and/or visual)
It is more difficult to bond to dentin than enamel because: A. dentin contains more mineralized tooth structure B. dentin contains more water C. the presence of the smear layer makes it harder for the adhesive to wet the dentin D. two of the above E. All of the above
D. two of the above B. dentin contains more water C. the presence of the smear layer makes it harder for the adhesive to wet the dentin
If a small pulpal exposure occurs during cavity preparation and is not due to caries (mechanical pulp exposure), a layer of ......, can be placed over the exposure site to stimulate ...... across the exposure site. This procedure is called ....
Dycal, reparative dentin, direct pulp capping
True or False: When using rubber points to polish amalgam, it is important to use the high speed handpiece because high rotational speed of the point is necessary to remove the remaining small voids and scratches that are present after using the finishing burs.
FALSE
True or False: Inadequate isthmus width is the most likely cause for isthmus fracture of Class II amalgam
FALSE (DEPTH)
Regarding light curing of composite resin, which of the following statements are true 1. The tip of the curing light should be within 2 mm of the composite surface 2. It is recommended that no more than 1.5-2 mm increments be light-cured at a time. 3. The degree-of-conversion (or degree of cure) is related to both the intensity of the light and duration of exposure. 4. Most light-curing requires a minimum of 20 seconds for adequate curing under optimal conditions of access. 5. Using a hand held curing light, most dental composites can be cured to levels of 75% degree of conversion of the reactive monomer sites. A. all statements are true B. 2, 3, 5 C. 2, 3, 4 D. 1, 2, 4, 5 E. 1, 2, 3, 4
E. 1, 2, 3, 4 1. The tip of the curing light should be within 2 mm of the composite surface 2. It is recommended that no more than 1.5-2 mm increments be light-cured at a time. 3. The degree-of-conversion (or degree of cure) is related to both the intensity of the light and duration of exposure. 4. Most light-curing requires a minimum of 20 seconds for adequate curing under optimal conditions of access. 5 not true because Using a hand held curing light, most dental composites can be cured to levels of 60% degree of conversion of the reactive monomer sites.
**Supplemental retention on abutment teeth is made possible by A. parallel alignment B. greater bulk of metal C. proper cementing technique D. a chamfer-type preparation E. proper use of grooves and box forms
E. proper use of grooves and box forms
True or False: Affected dentin has bacteria present, is not remineralized and does not need to be removed.
FALSE
True or False: Base materials are needed under composite resin restorations to provide thermal insulation
FALSE
True or False: Base materials are needed under composite resin restorations to provide thermal insulation.
FALSE
True or False: Enamel permeability decreases with age because of changes in the enamel matrix.
FALSE
True or False: In a Class I amalgam cavity preparation retention form is provided by mesial and distal walls that converge occlusally ???
FALSE
True or False: Polishing of low-copper amalgams is less important than it is for high-copper amalgams because the low-copper amalgams are less susceptible to tarnish and marginal breakdown.
FALSE
**True or False: When cementing an indirect composite veneer, the bonding agent is applied to the tooth surface of the veneer and cured before placing the veneer on the tooth to ensure complete polymerization of the bonding agent.
False
Dentin which forms in response to moderate-level irritants, such as attrition, abrasion, erosion, trauma, moderate-rate dentinal caries, and some operative procedures is called...
Reparative dentin
...... are probably the most important organism in the initiation of enamel caries.
Streptococcus mutans
True or False: Conservative amalgam restorations which have anatomy carved too deep can result in acute angles and stress concentrations within the amalgam increasing the potential for fracture.
TRUE
True or False: For conservative Class 1 amalgam preparations, besides varnish and bonding agent, a dentin desensitizer can be placed in the preparation to seal the prepared dentin before amalgam condensation.
TRUE
True or False: Mature plaque is primarily anaerobic
TRUE
True or False: Medium sized self-threading pins may elicit an inflammatory response if placed within 0.5 mm of the pulp, whereas slot placement does not.
TRUE
True or False: Mercury can be drawn to the surface of set amalgam during polishing procedures if improper use of rotary instruments (polishing cups and points) raises the temperature of the amalgam.
TRUE
True or False: Pain on percussion suggests possible injury to the periodontal membrane from pulpal or periodontal inflammation.
TRUE
True or False: The reaction that occurs in a mixture of Zinc Phosphate Cement (ZnPO4) is exothermic.
TRUE
True or False: Dentin bonding agents are being recognized as beneficial for dentinal sealing under any type of restorative material
True
Color differences in the dentin cannot be used as a reliable index for complete caries removal. In rapidly advancing lesions the softened dentin may show little or no color change while more slowly advancing lesions may have more discoloration. a. both statements are true b. both statements are false c. statement one is true; statement two is false d. statement one is false; statement two is true
a. both statements are true
Darker shades and microfilled composites are more difficult to cure because filler particles and coloring agents tend to scatter or absorb the curing light in the first 1 to 2 mm of material. a. both statements are true b. both statements are false c. statement one is true; statement two is false d. statement one is false; statement two is true
a. both statements are true
Pin retention is used more frequently in preparations with few or no vertical walls. Slots are particularly indicated in short clinical crowns and in cusps that have been reduced 2-3 mm for amalgam. a. both statements are true b. both statements are false c. statement one is true; statement two is false d. statement one is false; statement two is true
a. both statements are true
Spherical amalgam have higher earlier strength (when compared to admixed). Admixed amalgam permit easier proximal contact development because of higher condensation forces. a. both statements are true b. both statements are false c. statement one is true; statement two is false d. statement one is false; statement two is true
a. both statements are true
The reason for using traditional liners or bases is to either protect the pulp or to aid pulpal recovery or both. The remaining thickness of dentin is a key determining factor in material choice. a. both statements are true b. both statements are false c. statement one is true; statement two is false d. statement one is false; statement two is true
a. both statements are true
**An internal wall is a prepared cavity surface that does not extend to the external tooth surface. An internal wall that is parallel with the long axis of the tooth is called....
axial wall
To increase the diameter of the matrix band, the operator should turn the ..... on the matrix retainer .... A. adjusting nut, clockwise b. locking nut, counterclockwise c. adjusting nut, counterclockwise d. locking nut, clockwise
c. adjusting nut, counterclockwise
The enamel is thicker at the incisal and occlusal areas of a tooth and becomes progressively thinner until it terminates at the DEJ a. both statements are true b. both statements are false c. statement one is true; statement two is false d. statement one is false; statement two is true
c. statement one is true; statement two is false
Whenever possible, a syringe should be used for placing composite resin because a. the need for etching procedures is eliminated b. the need for applying enamel bonding agent is eliminated c. the possibility of trapping air in a restoration is minimized d. a syringe allows for less amount of composite material to be mixed
c. the possibility of trapping air in a restoration is minimized
Purported advantages of amalgam bonding include which of the following: a. increased retention of amalgam restorations b. reduction/prevention of post-placement leakage c. reduction/prevention of post-placement sensitivity d. all of the above e. none of the above
d. all of the above
Regarding a carbide bur, the number of cutting blades determines its cutting efficiency. Burs with a fewer number of cutting blades results in a. less efficient cutting and a smoother surface b. less efficient cutting and a rougher surface c. more efficient cutting and a smoother surface d. more efficient cutting and a rougher surface
d. more efficient cutting and a rougher surface
Primary resistance form is that shape or form of the prepared cavity that resists displacement or removal of the restoration from tipping or lifting forces. In Class II preparations where only one of the two proximal surfaces is involved, an occlusal dovetail may aid in preventing the tipping of the restoration by occlusal forces. a. both statements are true b. both statements are false c. statement one is true; statement two is false d. statement one is false; statement two is true
d. statement one is false; statement two is true
Resistance to proximal displacement in the ideal Class II amalgam restoration is provided by 1. the adjacent tooth 2. occlusal dovetail 3. converging proximal walls 4 retention grooves in proximoaxial line angles a. 1, 2, and 3 b. 1, 2 and 4 c. 1 and 3 d. 2 and 3 e. 2 and 4
e. 2 and 4
When placing pins to enhance retention form of a prepared cavity, which of the following potential pin sites should be avoided? a. the mid-buccal area of the mandibular first molar b. the mid-mesial area of the maxillary first premolar c. the mid mesial area of the maxillary first molar d. two of the above e. all of the above
e. all of the above
Name the hand instrument which can most effectively round the axiopulpal line angle and remove unsupported enamel rods at the gingival cavosurface margin of a Class II cavity prepared for amalgam
gingival margin trimmer
Whenever dentin has been cut or abraded, a thin altered surface is created called the.....
smear layer
What is the main reason pilot holes are used when preparing pin holes?
to prevent drill "crawling"
