Dentistry - Unit 10

Which of the following correctly describes the lagomorph dental formula? a. 2 × {I 2/1:C 0/0:P 3/2:M 3/3} b. 2 × {I 3/3:C 1/1:P 4/4:M 2/3} c. 2 × {I 3/3:C 1/1:P 3/2:M 1/1} d. 2 × {I 3/3:C 1/1:P 3/3}

a 2 × {I 2/1:C 0/0:P 3/2:M 3/3} is the rabbit formula; 2 × {I 3/3:C 1/1:P 4/4:M 2/3} is the permanent formula for dogs; 2 × {I 3/3:C 1/1:P 3/2:M 1/1} is the permanent formula for cats; 2 × {I 3/3:C 1/1:P 3/3} is the primary formula for dogs. Gorrel C, "Anatomy of the teeth and periodontium," Veterinary Dentistry for the General Practitioner, ed 2, Elsevier, 2013, p. 36-41.

Which of the following statements is true regarding the teeth of equine patients? a. Brachydont teeth fully erupt before maturity and are normally long and hard enough to survive for the life of the individual. b. Brachydont teeth do not fully erupt before maturity; however, they are hard enough to survive for the life of the individual. c. Brachydont teeth fully erupt before maturity; however, they are not hard enough to survive for the life of the individual. d. Hypsodont teeth do not have a limited time of growth.

a Brachydont teeth (permanent dentition) fully erupt before maturity and are normally long and hard enough to survive for the life of the individual because they are not subjected to the prolonged and high levels of dietary abrasive forces with which herbivore teeth must contend. In contrast, hypsodont teeth slowly erupt during most of a horse's life at a rate of 2-3 mm/year, which is similar to the rate of attrition (wear) on the occlusal surface of the tooth, provided that the horse is on a grass diet (or some alternative fibrous diet, e.g., hay or silage) rather than being fed high levels of concentrate food. The latter type of diet reduces the rate of occlusal wear and also restricts the range of lateral chewing actions and thus dental overgrowths can occur. Both brachydont and hypsodont teeth have a limited growth period (although this period is very prolonged in the latter group) and thus are termed anelodont teeth. Dixon, PM, duToit, N, "Dental anatomy," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 51-76.

Which of the following antiseptics is considered choice oral rinses for horses? a. Chlorhexidine gluconate b. Chlorhexidine acetate c. Dilute betadine d. Glutaraldehyde

a Chlorhexidine gluconate 0.05% (1:40 dilution of the 2% concentration) is the antiseptic of choice for oral rinses and has replaced chlorhexidine acetate because it is less likely to irritate mucous membranes. Dilute Betadine should not be used and glutaraldehyde can cause tissue necrosis. Galloway, SS, Galloway, MS, "Dental materials," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 345-368.

Which material is used to fill the pulp chamber inside the tooth during root canal therapy? a. Gutta percha b. Dental cement c. Calcium hydroxide d. Acrylic resin

a Gutta percha is used during a root canal procedure. After the pulp chamber has been debrided and flushed, a CE end or paste is used to seal the walls of the pulp chamber, preventing any bacteria from entering the dentinal tubules. Gutta percha fills in the remaining space in the pulp chamber. The gutta percha is packed into the pulp chamber using a plugger and a spreader. The spreader moves the gutta percha to the walls to allow more to be fitted in. Calcium hydroxide is an endodontic material used for a vital pulpotomy procedure. This material is placed on the exposed pulp and the tooth is restored. The material acts as an irritant to the tooth and causes it to form a dentist bridge over the exposed pulp, sealing it from any possible bacteria. The restoration is made from an acrylic resin. It acts as a permanent covering over any exposed tooth. The material comes in a paste or liquid form and is hardened and shaped to the tooth surface either by chemical curing or light bonding. Bellows J, "Endodontic equipment, materials, and techniques," Small Animal Dental Equipment, Materials and Techniques: A Primer, Blackwell, 2004, p. 175-229; Holmstrom SE, "Advanced veterinary dental procedures: periodontal surgery, endodontics, restorations and orthodontics," Veterinary Dentistry: A Team Approach, ed 2, Saunders, 2013, p. 307-342.

Equine cheek teeth are used primarily for: a. Grinding and mastication b. Prehension and cutting of food c. Defense and offense d. All of the above

a In horses, premolars 2-4 (Triadan 06-08) and the three molars (Triadan 09-11) can be collectively termed cheek teeth. Each type of tooth has certain morphological characteristics and specific functions. Incisor teeth are specialized for the prehension and cutting of food and the canine teeth are for defense and offence (for capture of prey in carnivores). Equine cheek teeth function as grinders for mastication. Dixon, PM, duToit, N "Dental anatomy," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 51-76.

The surface of the tooth toward the tongue is: a. Lingual b. Labial c. Buccal d. Mesial

a Lingual is the surface facing the tongue and is used in reference to the mandibular teeth. The most rostral surface is known as the labial aspect or toward the lips. The buccal surface is the side of the tooth that comes into contact with the cheek mucosa. The mesial surface is the part closest to the midline of the arch. The midline is the interdental space between the right and left maxillary and mandibular first incisors. Holzman G, "The basics," in Perrone JR, ed, Small Animal Dental Procedures for Veterinary Technicians and Nurses, Wiley-Blackwell, 2013, p. 3-22.

Which teeth are the most appropriate for determining the age of horses? a. Incisors b. Wolf teeth c. Premolars d. Molars

a The most appropriate teeth for aging horses are the (lower) incisors. The premolars and molars can be used with considerable accuracy to determine the horse's age, but their distal position has limited their use. Research has shown that cheek teeth morphology data can be used to predict age in horses that possess all permanent dentition. Radiographic assessment of cheek teeth root morphology can also help in determining age, especially in young horses. Because contact between upper and lower canines is seldom made, the canines do not wear down in a regular way and have no age-related occlusal surface. Dixon, PM, duToit, N "Dental anatomy," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 51-76.

All of the following factors must be considered when aging a horse except: a. Breed b. Quantity of food c. Environmental conditions d. Injury

b A variety of factors such as nature and quality of food, environmental conditions, heredity, injury, and disease can influence dental wear. It is, therefore, important that equine clinicians do not claim levels of accuracy that are unjustifiable. As it is impossible to assign specific ages to each dental feature, accuracy of age estimation in certain individuals can be very low. Dixon, PM, duToit, N "Dental anatomy," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 51-76.

How many incisors are present in the adult equine patient? a. 6 b. 12 c. 24 d. 36

b Adult horses also have 12 incisors in total, 6 in each arcade. The upper incisor teeth are embedded in the premaxillary (incisive) bone and the lower incisors in the rostral mandible, with the reserve crowns and apices of incisors converging toward each other. Dixon, PM, duToit, N, "Dental anatomy," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 51-76.

Parrot mouth in foals is also known as an: a. Underbite b. Overbite c. Overjet d. Underjet

b Foals develop a number of growth abnormalities, one being parrot mouth or an overbite. Overjet is known as overshot jaw, which will result in an overbite when not treated. Underjet is also known as undershot jaw and it is rare. Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 51-76.

How many deciduous teeth do horses have? a. 20 b. 24 c. 36 d. 44

b Horses have 24 deciduous teeth 2(Di 3 / 3, Dc 0 / 0, Dm 3 / 3). Dixon, PM, duToit, N, "Dental anatomy," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 51-76.

When using motorized equipment for an equine prophylaxis, which speed should be used to prevent thermal damage? a. 100-200 rpm b. 2000-3000 rpm c. 3000-4000 rpm d. 4000-5000 rpm

b If used improperly, all motorized floats can overheat teeth to the point of pulp damage. Lower speeds in the 2000 to 3000 rpm range are preferred because higher-speed rotation produces heat faster. (Note: Use light pressure on the float and keep it moving.) Easley J, Rucker, BA, "Equine dental equipment, supplies and instrumentation," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 245-260.

The purpose of polishing during the dental prophy is to: a. Massage the gums b. Smooth out the rough areas and retard plaque formation c. Apply fluoride d. Disinfect the surface of the tooth

b Scaling the teeth causes microetchants on the surface of the enamel, therefore polishing paste is applied to smooth the surface of the tooth and to remove any remaining plaque left behind by the cleaning. The polishing cup runs only over the surface of the teeth, not the gums. The polish does not disinfect and fluoride is not applied after polishing. Bellows J, "Equipping your dental practice," The Practice of Veterinary Dentistry, Iowa State Press, 1999, p. 45-80.

At what age do premolars erupt in foals? a. Foals are born with teeth b. 5-7 days after birth c. 3-4 weeks after birth d. 3-4 months after birth

b The 12 temporary premolars (506-508, 606-608, 706-708, and 806-808) erupt at birth or do so within a week. Dixon, PM, duToit, N, "Dental anatomy," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 51-76.

An adult equine mouth normally contains ______ cheek teeth. a. 12 b. 20 c. 24 d. 34

c An adult equine mouth normally contains 24 cheek teeth (06s-11s, i.e., 2nd-4th premolars and 1st-3rd molars), forming four rows of six teeth that are accommodated in the maxillary and mandibular bones. The molars erupt at approximately 1, 2, and 3.5 years of age, respectively. Dixon, PM, duToit, N, "Dental anatomy," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 51-76.

In horses, the term coronal refers to which portion of the tooth? a. The area of the tooth farthest away from the occlusal surface b. The area closest to the tongue c. The crown d. The tooth closest to the incisors

c Coronal refers to the crown. The area furthest away from the occlusal surface is the apical surface. The area closest to the tongue is the lingual surface and the tooth closest to the incisors is the premolar. Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 51-76.

All of the following instruments may be used to remove deciduous cheek tooth remnants except: a. Forceps b. Forceps c. Gelpi retractors d. Dental picks

c Gelpi retractors are used in abdominal surgery to expose the abdominal cavity. Various forceps, elevators, and dental picks should be available to remove retained, displaced, or broken deciduous cheek tooth remnants (caps). Easley, J, Rucker, BA, "Equine dental equipment, supplies, and instrumentation," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 245-260.

Canine teeth are always present in which of the following patients? a. Donkeys b. Female horses c. Male horses d. All of the above

c Male horses normally have four permanent canine teeth: two maxillary and two mandibular. Canine teeth are usually absent or rudimentary in female horses, with a reported prevalence of 7.8%-28% in horses and 17.3%-30% in donkeys. Dixon, PM, duToit, N, "Dental anatomy," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 51-76.

Which of the following instruments should be used to reduce the crown of sharp canine teeth? a. Nippers b. Cutters c. Small files d. Elevators

c Nippers and cutters should not be used on canine teeth because these instruments offer minimal to no control during tooth fracturing. Opening the pulp or dentinal tubules can lead to pulpitis and tooth death years after the reduction. To avoid over-reduction of the canines, small files or diamond disc grinders (at low speed) should be used only for smoothening or to blunt the top of the canine. Elevators are not used to smooth tooth surfaces. Easley, J, Rucker, BA, "Equine dental equipment, supplies, and instrumentation," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 245-260.

Teeth that grow throughout an equine patient's life are termed: a. Brachydont b. Hypsodont c. Anelodont d. Elodont

d Elodont teeth grow continually throughout all of an animal's life. Brachydont and hypsodont teeth are considered anelodont and have a period of growth. Dixon, PM, duToit, N, "Dental anatomy," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 51-76.

The most common dental procedure performed on a horse is: a. Quidding b. Curettage c. Scaling d. Floating

d Horses have teeth that can develop sharp points if they do not chew their food properly. Eating wears the teeth down, causing sharp edges to form. Floating is the filing or rasping of a horse's premolar and molar teeth to remove the sharp edges. This procedure should be performed on a regular basis to avoid oral pain. Quidding is the dropping of food while chewing, often a sign that the teeth need to be examined. Curettage, scaling, and dental radiographs are also available for equine patients. http://vetmedicine.about.com/od/equinehorseinformation/f/FloatingHorseTeeth.htm.

All of the following are common non-neoplastic conditions seen in the oral cavity of horses except a. Cementoma b. Polyps c. Papilloma d. Epulis

d Polyps, papillomas, and epulides are all non-neoplastic masses, whereas a cementoma is an odontogenic neoplasm. Knottenbelt, DC, Kelly, DF, "Oral and dental tumors," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 149-184.

All of the following are common soft-tissue neoplasms seen in horses except: a. Squamous cell carcinoma b. Sarcoid c. Ossifying fibroma d. Osteoma

d SCC, sarcoid, and ossifying fibroids are all soft tissue neoplasms, whereas an osteoma is an osteogenic neoplasm. Knottenbelt, DC, Kelly, DF, "Oral and dental tumors," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 149-184.

Which of the following safety items should be used when operating motorized dental instruments on the equine patient? a. Protective eyewear b. Air filter mask c. Ear protection d. All of the above

d Safety of the operator, the assistant(s), and the equine patient during motorized instrument use can be optimized in several ways. Protective eyewear and an air filter mask reduce the chance of debris and tooth dust entering the eyes and/or being inhaled. Ear protection should be considered if loud electric motors are used close to the operator's head or noisy air compressors are in operation nearby. Easley, J, Rucker, BA, "Equine dental equipment, supplies, and instrumentation," in Easley J, Padraic Dixon P, Schumacher J, Equine Dentistry, ed 3, Elsevier Health Sciences, 2011, p. 245-260

The heaviest calculus deposition in dogs and cats is typically located on the: a. Lingual surfaces of the lower cheek teeth b. Lower canine teeth c. Incisor teeth d. Buccal surfaces of the upper cheek teeth

d The heaviest calculus is usually found on the buccal surface of the upper check teeth because of the adjacent parotid salivary duct opening. The opening or parotid papilla is located in the mucosa above the distal root of the maxillary fourth premolar. The lower canine and incisor teeth are not adjacent to any salivary glands. There are two molar salivary glands in cats, which are the lingual molar salivary gland and the buccal molar salivary gland. These are not present in dogs. Wiggs RB, Lobprise HB, "Oral anatomy and physiology," in Veterinary Dentistry: Principles and Practices, Lippincott-Raven, 1997, p. 55-86.