Dentistry PDF

dentistry 1. What is dental calculus made of? Mineralized plaque | Sloughed tooth fragments | Calcified food debris | Gingival epithelium | Bacterial debris Mineralized plaque Dental calculus is mineralized plaque. Plaque is the whitish-yellow film that accumulates in the gingival sulcus (the cl...

dentistry 1. What is dental calculus made of? Mineralized plaque | Sloughed tooth fragments | Calcified food debris | Gingival epithelium | Bacterial debris Mineralized plaque Dental calculus is mineralized plaque. Plaque is the whitish-yellow film that accumulates in the gingival sulcus (the cleft between the gums and the tooth). It is made up of food debris, saliva glycoproteins, exfoliated cells, and bacteria. Bacterial plaque on the tooth surface commonly triggers gingivitis. With time, plaque builds up and mineralizes into calculus. Ref: Cote, Clinical Veterinary Advisor: Dogs and Cats, 4th ed., pp. 776-8 and Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1237. 2. What percentage of cats will have periodontal disease by two years of age? 95% | 55% | 70% | 30% 70% Approximately 80% of dogs and 70% cats will have periodontal disease (around="peri", "dontal"=teeth) by two years of age. The point is that this is a COMMON problem. Periodontal disease is a general term that includes gingivitis (gum inflammation) and peridontitis (more chronic, severe damage from bacterial plaque that involves gingiva, periodontal ligament, alveolar bone, root cementum). Periodontal disease is caused by accumulation of bacterial plaque at the gingival margin (gumline) due partly to lack of adequate oral hygiene. Follow these links to see gingivitis in a dog, a radiograph of peridontitis with bone loss, and peridontitis in a dog. Refs: Tighe and Brown, Mosby's Comprehensive Review for Veterinary Technicians, 4th ed. p. 629. 3. How many permanent teeth are found in a normal horse? 18-24 | 36-44 | 20-30 | 28-32 | 28-48 36-44 Adult horses vary between 36 and 44 permanent teeth, depending upon whether they have canines and/or wolf teeth. Cats have 30 permanent teeth. Ruminants are in the middle between cats and dogs with 32. Dogs have 42 permanent teeth. Food- loving pigs have the most teeth at 44. Follow these links to see a diagram of normal horse dentition and a dental formula table for large and small animals. Refs: Tighe and Brown, Mosby's Comprehensive Review for Veterinary Technicians, 4th ed. p. 631. 4. The veterinarian diagnoses a dog with gingivitis. What is the problem? Irritated eyes | Tooth root infection | Epiglottal inflammation | Creeping eruptions | Inflamed gums Inflamed gums Gingivitis is inflammation of the gums. Look for reddening at the base of the teeth. Follow these links to see gingivitis in a dog. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1236. 5. Infection of the roots of which teeth in a horse can lead to sinusitis and chronic unilateral nasal discharge? The upper wolf teeth | None can do this | The central upper and lower incisors | The caudal 4 maxillary cheek teeth | The rostral 2 mandibular molars The caudal 4 maxillary cheek teeth The roots of the four caudal maxillary cheek teeth (4th premolar; 1st, 2nd, and 3rd molar) extend into the ventral aspect of the maxillary sinuses. Sinusitis can develop secondary to infection of these teeth. Sinusitis secondary to tooth root abscess often necessitates tooth extraction and sinus lavage for permanent resolution. Dr. David Ramey covers indications and complications of cheek teeth extractions in horses. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., pp. 268, 1265. 6. How many permanent teeth are found in a normal pig? 32 | 48 | 44 | 42 44 Food-loving pigs have the most teeth at 44. In cats there are 30 permanent teeth. Ruminants are in the middle between cats and dogs with 32. Dogs have 42 permanent teeth. Horses vary by age between 24-44. Follow these links to see a diagram of normal pig dentition and a dental formula table for large and small animals. Refs: Tighe and Brown, Mosby's Comprehensive Review for Vet Techs, 3rd ed. p. 492. 7. What is the peridontium? The part of the teeth below the gumline | The structures that support the tooth | The part of the teeth visible above the gumline | The periodontal ligament and alveolar bone beneath it The structures that support the tooth The peridontium is another name for all the structures that SUPPORT a tooth. These include the gums, the tooth root cementum, the periodontal ligament and the alveolar bone of the jaw to which the ligaments attaches. Follow this link to see a tooth cross-section diagram. Refs: Bassert and Thomas, McCurnin's Clinical Textbook for Veterinary Technicians, 8th ed. p. 1321 and Wikipedia online. 8. Which of these dental instruments is blunt? Curette scaler | Periodontal probe | Shepherd's hook | Sickle scaler | Periosteal elevator Periodontal probe A periodontal probe is blunt, and is used to gently measure the depth of the gingival sulcus. Scalers have two parallel sharp sides, used for supragingival calculus removal. A curette scaler has one sharp side and is used for subgingival calculus removal. A shepherd's hook has a sharp tip and is used to detect cavities and broken teeth. A periosteal elevator is used during orthopedic surgeries to separate the periosteum from the bone. Dr. Jan Bellows describes Dental Probes and Explorers and provides descriptions of both. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1230. 9. Which choice is a distinctive feature of brachydont teeth? Crown surface is much larger than the apex | Dark tooth enamel | Large reserve crown beneath the gingival margin | Permanent teeth stop growing after eruption | Continual growth  Permanent teeth stop growing after eruption Humans, carnivores, and pigs have brachydont (low-crowned) teeth. The roots' apices are at the tip of the root, where cells can repeatedly divide and where all primary root tissue derives. Click here to see basic canine tooth anatomy. They are open only during eruption and tooth development. Brachydont teeth do NOT continually grow or erupt. In contrast, hypsodont teeth grow for most of the life of the animal. Continual growth helps to offset occlusal wear experienced by adult teeth of grazing animals (e.g., horses, ruminants). Hypsodont teeth have a large reserve crown beneath the gingival margin, and the tooth apices remain open for a large portion of the adult animal's life, though they do eventually close and tooth growth stops. This article from Colorado State University provides a useful description and images of different teeth. Here is a fun review of the diversity of kinds of teeth that animals have evolved with everything from gazelles (selenodont) to golden moles (zalambodont). Ref: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed. p. 1218. 10. What is the most common malignant oral tumor in dogs? Squamous cell carcinoma | Osteosarcoma | Transitional cell carcinoma | Fibrosarcoma | Melanoma Melanoma Malignant melanoma is the most common oral malignant tumor in dogs, but you can never tell simply by looking at the animal what kind of growth it may be. It takes a biopsy to confirm the diagnosis. Follow this link to see a malignant melanoma on a dog's lip and a cat's radiograph of malignant melanoma (note the jaw bone and teeth are dissolved away!). Squamous cell carcinoma is by far the most common oral malignant tumor in cats and the second most common in dogs. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1262. 11. What is the normal depth of the gingival sulcus in dogs? 1-3 mm | > 10 mm | Normal dogs do not have a gingival sulcus | 4-7 mm | 0.5-1 mm 1-3 mm Normal depth of the gingival sulcus in dogs is 1-3 mm, and in cats is less than 1 mm. The gingival sulcus is the crevice between the tooth and the gumline where plaque collects. It is important to know that this crevice is not very deep in normal cats when you are cleaning teeth. Dr. Jan Bellows describes the uses of Dental Probes and Explorers Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1232. 12. A six-month-old mixed breed dog is presented with a retained deciduous canine tooth. It does not feel loose. Which one of the following choices is the best recommendation? Tie a suture to the tooth and pull hard | Remove the tooth now using an open approach | Wait until the dog is at least a year old then remove the tooth | Perform a root canal | Leave it alone, it is too early to tell if it won't fall out on its own Remove the tooth now using an open approach It is best to remove the retained deciduous tooth (also called "persistent deciduous teeth") as soon as possible to prevent periodontal disease, malocclusion, and trauma to the lips. Since it does not feel loose, an open approach is recommended, as root fracture and retained root tips are possible complications. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1260 and Cote, Clin Vet Advisor 3rd ed. pp. 258-9. Image courtesy, Nottingham Vet School. 13. In which breeds is the primary problem seen in this image considered to be normal? Click here to see image Click here to see image None. This is always abnormal | Collies | Chondrodystrophics | Brachycephalics | Toy breeds Brachycephalics This dog has mandibular prognathia (a.k.a. under-bite or mandibular mesioclusion), which is considered normal in brachycephalic dogs. The mandible is longer than the maxilla. Check out the American Veterinary Dental College's terminology here. Refs: Côté, Clinical Veterinary Advisor: Dogs and Cats, 4th ed., p. 617 and Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1259. 14. Which one of the following choices can cause enamel hypoplasia in the dog? Severe giardiasis | Canine adenovirus-1 vaccination | Neosporosis | Heartworm infection | Distemper Distemper Distemper virus. Enamel hypoplasia is the incomplete or defective formation of tooth enamel. Causes include trauma, systemic (fever, distemper), nutritional deficiencies (hypocalcemia), fluorosis, tetracyclines, and hereditary (rare). Click here to see a dog with enamel hypoplasia. Enamel hypoplasia occurs only during the formative stage of enamel development (amelogenesis), before tooth eruption into the oral cavity. Here are crown formation dates for dogs and cats: Primary teeth: day 42 gestation to day 15 postpartum Permanent teeth: week 2 to 3rd month postpartum. Ref: Gorrel, Saunders Small Anim Dent, pp.197-200. 15. What is the most important reason to polish an animal's teeth after a dental cleaning? Remove excess gingiva | Scale tooth roots | Remove big pieces of calculus | Smooth small scratches on the tooth surface | Scale the crowns of the teeth Smooth small scratches on the tooth surface Polishing smooths down small pits and scratches left after scaling procedure and from routine chewing. Polishing slows the return of plaque by decreasing the available surface area created by scratches. Alex Smithson covers the role of polishing in veterinary dentistry Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1246. 16. How many permanent teeth are found in a normal adult goat? 30 | 42 | 40 | 32 | 24 32 Ruminants (cows, sheep, goats) are in the middle between cats and dogs with 32. In cats there are 30 permanent teeth. Dogs have 42 permanent teeth. Food-loving pigs have the most teeth at 44. Horses vary between 36-44. Follow these links to see a diagram of normal sheep and goat dentition and a dental formula table for large and small animals. Refs: Tighe and Brown, Mosby's Comprehensive Review for Veterinary Technicians, 4th ed. p. 631. 17. What is the numerical classification for the canine tooth in the right maxilla in dog? 205 | 104 | 305 | 404 | CUR4 104 There are two slightly different tooth numbering systems, the anatomical and the Triadan systems, but they both number the canines and incisors the same way. This chart shows the modified Triadian system for the dog. The upper right canine is 104. The lower right canine is 404. The upper left canine is 204. The lower left canine is 304. The first upper left premolar is 205. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1219-1220. 18. A two-month-old male mixed breed puppy is presented with a fever (104°F, 40°C [N=100.2–102.5°F; 37.9-39.2°C]), crusty oculonasal discharge, labored breathing, coughing, vomiting and diarrhea, anorexia, and lethargy. The presumptive diagnosis is canine distemper virus infection. What sequelae may be seen when permanent teeth come in? Gingival hypertrophy | Enamel hypoplasia | Retained deciduous teeth | Anodontia | Epulis formation Enamel hypoplasia Distemper causes enamel hypoplasia in permanent teeth if the dog is infected between two weeks and three months of age. Because distemper is a systemic disease, the entire dentition is affected. If infected between late-stage gestation and two weeks postpartum, only the deciduous teeth are affected. Dr. Brett Beckman discusses dental enamel defects in dogs. Refs: Cote, Clinical Veterinary Advisor: Dogs and Cats, 4th ed., pp. 271-3. 19. Which of the following are best radiographed using the bisecting radiograph technique? All deciduous teeth | Maxillary incisors | Mandibular premolars | Temporomandibular joints (TMJ) | Mandibular molars Maxillary incisors The bisecting radiograph technique is generally preferred for all teeth EXCEPT for the mandibular premolars 3 and 4, and the molars. Mandibular cheek teeth for horses are composed of molars and premolars. Bisecting radiograph technique minimizes the image distortion that occurs because of an inability to place x-ray film parallel to the central axis of a tooth. If you do not use the bisecting angle technique, a tooth may appear artificially foreshortened or elongated. The idea is easier to understand with a picture. Click here to see a good summary article with images of bisecting technique, courtesy of the Veterinary Dentistry website from Dr. Norman Johnston and the Royal Veterinary College of London. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1234 and Tighe and Brown, Mosby's Comprehensive Review for Veterinary Technicians, 4th ed. p. 641. 20. What image problems are avoided with proper bisecting radiograph technique of teeth? Increased scatter | Overlap of soft tissue | Elongation | Decreased contrast Elongation The bisecting radiograph technique minimizes the image distortion that occurs because of an inability to place x-ray film parallel to the central axis of a tooth. If you do not use the bisecting angle technique, a tooth may appear artificially foreshortened or elongated. The bisecting radiograph technique for generally preferred for maxillary teeth and mandibular canines and incisors (the rostral mandibular teeth). Bisecting radiograph technique minimizes the image distortion that occurs because of an inability to place x-ray film parallel to the central axis of a tooth. If you do not use the bisecting angle technique, a tooth may appear artificially foreshortened or elongated. The idea is easier to understand with a picture. Click here to see a good summary article with images of bisecting technique, courtesy of the Veterinary Dentistry website from Dr. Norman Johnston and the Royal Veterinary College of London. Refs: Bassert and Thomas, McCurnin’s Clinical Textbook for Veterinary Technicians, 8th ed. pp. 1319-20, figures 34-26, 34-28 and Tighe 1319-20, Brown, Mosby's Comprehensive Review for Vet Techs, 3rd ed. p. 499. 21. What is the correct term for the side of the tooth that faces the cheek? Palatal | Gingival | Labial | Lingual | Buccal Buccal The buccal side of the tooth faces the cheek. Lingual side faces the tongue. Labial surface of the tooth is nearest the lips. Gingival is the area of the tooth toward gums. Palatal surface is towards the roof of the mouth. Ref: Tighe and Brown, Mosby's Comprehensive Review for Veterinary Technicians, 4th ed. p. 631. 22. Which of these protect teeth from bacteria? Enamel and cementum | Enamel and dentin | Periodontal ligament and cementoenamel junction | Sulcular fluids and pulp | Dentin and pulp Enamel and dentin Bone-like enamel and dentin are physical bacterial barriers. Sulcular fluid has antimicrobial properties (contains immunoglobulins) and flushes the sulcus (crevice area between gumline and neck of a tooth). Pulp does not have particular antibacterial properties. The periodontal ligament is the attachment between a tooth and the bone, and the cementoenamel junction is the transition between the crown and the root. Follow this link to see a tooth cross-sectional diagram. Refs: Tighe and Brown, Mosby's Comprehensive Review for Veterinary Technicians, 4th ed. p. 629-630 and Wikipedia Commons. 23. When cats develop gingivitis, which pathogenic bacteria play a more important role? Gram-negative rods | Staphylococcus intermedius | Aerobes | Gram-positive cocci | Pseudomonas aeruginosa Gram-negative rods As cats develop gingivitis, gram-negative bacteria play a more important role in addition to the anaerobes. In treating oral disease, it becomes important to add an antibiotic with gram-negative spectrum as dental disease progresses. Refs: Cote, Clinical Veterinary Advisor-Dogs and Cats, 3rd ed. pp. 794-6. 24. In what animals are the “fighting teeth” (i.e., upper and lower canines) routinely ground down as needed in intact males? Llamas | Horses | Cats | Dogs | Cattle Llamas Llamas and alpacas have “fighting teeth”; i.e., the upper 3rd incisor and upper and lower canine teeth, which can grow to over 3 cm in length and cause severe trauma. These are usually ground down or removed upon eruption at 18–24 months. Anesthesia should be used for this procedure as it is quite painful. It must be repeated at intervals as these teeth continue to grow. When only the tips are cut off, this can be done without anesthesia and may be performed by the breeder. When the crown is removed, the root will be exposed. The stub of the crown can be covered with a gingival flap. However, this is not commonly done and complications are rarely seen. The canine teeth can also be completely extracted under general anesthesia. This is a fairly extensive procedure and is not often performed. Canine teeth in females are poorly developed. After castration, the canines of males will stop growing. Ref: Fowler's Medicine and Surgery of South American Camelids, 3rd ed. pp. 134-36. 25. What is the most common malignant oral tumor in cats? Fibrosarcoma | Squamous cell carcinoma | Transitional cell carcinoma | Melanoma | Osteosarcoma Squamous cell carcinoma Squamous cell carcinoma is by far the most common oral malignant tumor in cats and the second-most common in dogs. You cannot diagnose any mass by appearance alone. It takes cytology or a biopsy to confirm the diagnosis. Follow this link to see a squamous cell carcinoma. Malignant melanoma is the most common oral malignant tumor in dogs. Here is a malignant melanoma on a dog's lip and a radiograph of an oral malignant melanoma in a cat (note the jaw bone and teeth are dissolved away). Ref: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed. p. 1261. 26. What material is used to make the initial tooth impression during treatment planning for orthodontic disease in dogs and cats? Oral cement | Alginate | Periapical epoxy | Obturate | Dental luxator Alginate Alginate is used to make an initial impression of the teeth. Only apply alginate to clean teeth. Choose the appropriately sized dental tray and fill it with alginate to produce a negative impression of the entire mouth. A final positive image impression is made using dental stone. Ref: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed. p. 1259. 27. How common are dental caries (cavities) in cats? Seen in 85% of adults older than 5 years | Seen in 25% of adults older than 5 years | Rare | Common Rare Dental caries (cavities) are UNcommon in dogs and RARE in cats. This may be due to differences from humans in oral flora and diets that are mostly free of easily fermentable carbohydrates (ie: pets don't drink soda pop every day). Also, dogs have slightly alkaline saliva. In cats there is a poorly understood problem called Feline odontoclastic resorptive lesions, (FORL, or "neck lesions") where tooth material is resorbed around the "neck" of a tooth. Possibly infectious, but the actual cause is not yet known. Follow these links to see a radiograph of a severe neck lesion and a photo of the same tooth. Ref: The Merck Veterinary Manual online edition. 28. Into which two foramina (holes) is local anesthetic typically injected for dental nerve blocks in dogs and cats? Ovale and apical | Transverse and obturator | Greater sciatic and lesser Panizza | Vertebral and sacral | Mandibular and infraorbital Mandibular and infraorbital The mandibular foramen is used for infiltration of local anesthetic blocks in the lower jaw, and the infraorbital foramen is used to help block the upper jaw. For a 50-pound dog, 0.5 ml volume is appropriate; 0.1 ml is typically used for cats. The foramen ovale is found in the fetal heart and the apical foramen is a hole at the tip of a tooth root. The transverse foramen is an opening in the cervical vertebrae into which the artery enters, the obturator foramen is created where the ischium and pubis bones come together. The vertebral foramen is formed by the body of the vertebrae and the vertebral arch and the sacral foramen is where the sacral nerves pass through the sacrum. The greater sciatic foramen is found in the pelvis and the Panizza foramen is a hole connecting the two aortas after they leave the heart in crocodiles. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed. p. 991 and Wikipedia, Foramen. 29. Horses are typically about ____ year(s) old when they first have all of their permanent incisors. 2 years old | 7 years old | 5 years old | 1 year old | 3 years old 5 years old 5 years old. Deciduous incisors erupt in foals at approximately 1 week, 6 weeks, and 6 months (_01, _02, and _03, respectively, numbered by modified Triadan system). Permanent incisors erupt at approximately 2.5, 3.5, and 4.5 years (_01, _02, and _03, respectively). Refs: Guide for Determining the Age of the Horse, American Association of Equine Practitioners, Lexington, KY, 2002. 30. A 12-year-old female spayed domestic shorthair cat is presented with a progressive preference for wet food and drooling. The cat is sedated and a thorough oral examination shows the image seen below. Note that the cat is lying on its' back and the labeled teeth are maxillary. What problem is indicated by the arrow? Tooth resorption | Severe bacterial periodontitis | Unable to determine from this history and image | Enamel hypoplasia and hypomineralization | Ameloblastoma Tooth resorption This clinical history and image are consistent with tooth resorption, also known as feline odontoclastic resorptive lesions. In this image, there is a resorptive lesion on upper premolar 2, indicated by the arrow. With progression, resorption progresses into dentin and extends to the tooth crown where it undermines enamel and ultimately fracture can occur. Incidentally, there are also fractures of upper premolar 1 and the canine tooth, and plaque on upper premolar 3. Click here to see an image of very severe tooth resorption. Tooth resorption is common in cats over four years old, especially those with periodontal disease and excessive tartar. The cause is unknown. Premolars and molars are most commonly affected. Clinical signs vary from none to those seen in this cat, and can also include tooth chattering. Dx: Full examination under anesthesia. Full mouth dental radiographs are needed - lesions are often quite advanced before becoming clinically apparent. Rx: Surgical extraction of all affected teeth and root remnants of fractured teeth. The disease is progressive. Follow these links for a good visual tour of basic feline dentition and canine dentition and dental anatomy, courtesy of Colorado State School of Veterinary Medicine. Refs: Côté, Clinical Veterinary Advisor: Dogs and Cats, 4th ed., pp. 982-3. Image courtesy of Uwe Gille. 31. Which dental radiographic technique maximizes the area shown on the film, helps evaluate nasal disease, and is useful in identifying tooth remnants? Paralleling | Occlusal | Reverse | Long axis | Bisecting angle Occlusal These are attributes of the occlusal technique, in which the film is placed on the occlusal plane and the beam is directed at a right angle towards it. This is the least frequently used positioning technique. The paralleling technique directs the beam at a right angle to a film that is placed intraorally parallel to the long axis of the tooth. It can only be used on mandibular teeth due to the rostral symphysis of the mandible and the maxilla’s adjacent palate. The bisecting angle technique is used when paralleling is not possible. This technique directs the beam at a right angle to an imaginary line that bisects the angle formed by the long axis of the tooth and the plane of the film. Click to view a video on Radiographic Positioning. Ref: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed. pp. 492, 1220, 1234. 32. There are three kinds of ultrasonic scaler: magnetorestrictive, piezoelectric and sonic. What is the advantage of a piezoelectric scaler over the other two kinds? No pitting of enamel | Quieter | Least traumatic | No heat build-up Least traumatic Piezoelectric scalers are the least traumatic. Sonic dental scalers do not build up heat like the other 2 kinds of scalers. In order to avoid overheating or pitting damage to the tooth and enamel, do not apply ultrasonic scalers more than 5 sec. This is a general rule, and may depend on the kind of machine you use. Ref: Tighe and Brown, Mosby's Comprehensive Review for Vet Techs, 3rd ed. p. 494. 33. How common are dental caries (cavities) in dogs? Seen in 35% of adults older than 5 years | Uncommon | Common | Seen in 75% of adults older than 5 years Uncommon Dental caries (cavities) are UNcommon in dogs and RARE in cats. This may be due to differences from humans in oral flora and diets that are mostly free of easily fermentable carbohydrates (ie: pets don't drink soda pop every day). Also, dogs have slightly alkaline saliva. In cats there is a poorly understood problem called Feline odontoclastic resorptive lesions, (FORL, or "neck lesions") where tooth material is resorbed around the "neck" of a tooth. Possibly infectious, but the actual cause is not yet known. Follow these links to see a radiograph of a severe neck lesion and a photo of the same tooth Ref: The Merck Veterinary Manual online edition. 34. There are two types of ultrasonic dental scalers -- piezoelectric and magnetostrictive. What advantage does the magnetostrictive scaler offer over piezoelectric one? Produces more energy | Less fragile | Does not spray vaporized debris | Can be used as a separate hand scaler | Increased range of motion Less fragile Magnetostrictive transducers are less fragile than piezoelectric scalers because they are composed of thin metal strips as compared to a ceramic disc. A piezoelectric scaler can break if accidentally dropped. The magnetostrictive type of scaler is the most commonly used ultrasonic scaler in both veterinary and human dentistry. Ref: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed. pp. 1240-41. 35. What percentage of dogs will have periodontal disease by two years of age? 80% | 12% | 25% | 50% 80% Approximately 80% of dogs and 70% cats will have periodontal disease (around="peri", "dontal"=teeth) by two years of age. The point is that this is a COMMON problem. Periodontal disease is a general term that includes gingivitis (gum inflammation) and peridontitis (more chronic, severe damage from bacterial plaque that involves gingiva, periodontal ligament, alveolar bone, root cementum). Periodontal disease is caused by accumulation bacterial plaque at the gingival margin (gumline) due partly to lack of adequate oral hygiene. Follow these links to see gingivitis in a dog, a radiograph of peridontitis with bone loss, and peridontitis in a dog. Refs: Tighe and Brown, Mosby's Comprehensive Review for Veterinary Technicians, 4th ed. p. 629. 36. Which part of a tooth is the crown? Toward the tongue | Chewing surface | Towards the roof of the mouth | Above the gum line | Toward the cheek Above the gum line The crown is the visible tooth above the gum line. The chewing surface of a tooth is occlusal. Buccal means the surface toward the cheek. Lingual is surface toward the tongue. Palatal is towards the roof of the mouth. Refs: Tighe and Brown, Mosby's Comprehensive Review for Veterinary Technicians, 4th ed. p. 631. 37. Canine acanthomatous ameloblastoma is sometimes referred to by what general name? Odontogenic fibroma | Papilloma | Epulis | Odontoma | Malignant melanoma Epulis An acanthomatous ameloblastoma is also referred to as an epulis (plural = epulides), which is a general term for a gingival mass. It is an epithelial odontogenic tumor. Ameloblastomas often invade local tissues, including bone, but generally do not metastasize. Surgical excision is curative but must include one-cm margins of clinically normal tissue (including bone and teeth) to prevent recurrence. Often requires mandibulectomy/maxillectomy for definitive treatment. Radiation therapy is also effective, but can cause subsequent malignant tumor development in the irradiated area. Here is an image of an ameloblastoma, and a radiograph of an ameloblastoma. Px excellent if complete excision. Recurrence likely if margins are not clean. Peripheral odontogenic fibroma (previously fibrous epulis) is the most common canine benign oral tumor. They are typically slow growing and arise from the periodontal ligament. Surgical excision is typically curative. Refs: Cote, Clinical Veterinary Advisor: Dogs and Cats, 4th ed., pp. 306-9. 38. By what age should a cat have all its permanent teeth, and how many teeth are in the feline adult dental formula? 42 by 6 months | 44 by 20 months | 30 by 7 months | 36-44 by 5 years | 32 by 4 years 30 by 7 months Cats should have 30 teeth by 7 months of age. Ruminants have 32 by 4 years, horses 36-44 by 5 years, dogs 42 by 7 months, and pigs 44 by 20 months. Eruption times used to estimate ages are important to study--Follow this link to a Merck Manual tooth eruption table. Refs: The Merck Vet Manual online edition. 39. What is wrong with this rabbit? Click here to see image Click here to see image Diet too high in roughage | Malocclusion | Chronic calcium-phosphorus imbalance | Broken mandible, poorly healed | Oral damage from excessive cage chewing Malocclusion This is malocclusion of the incisors and they need to be carefully trimmed under anesthesia. Malocclusion is a common problem in animals whose teeth grow continuously throughout life, like rabbits and small rodents. Dental trimming in rabbits is done under anesthesia with bone or wire cutters, or with a grinding tool or dental burr (safer). Dental trimming in small rodents like mice, hamsters and gerbils can often be done with nail clippers or small scissors. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 788 and Quesenberry and Carpenter, Clin Med and Surg of Ferrets, Rabbits and Rodents, 3rd ed. pp. 457-59. 40. How many permanent teeth are found in a normal adult cow? 30 | 42 | 24 | 40 | 32 32 Ruminants (cows, sheep, goats) are in the middle between cats and dogs with 32. In cats there are 30 permanent teeth. Dogs have 42 permanent teeth. Food-loving pigs have the most teeth at 44. Horses vary between 36-44. Follow these links to see a diagram of normal cow dentition and a dental formula table for large and small animals. Refs: Tighe and Brown, Mosby's Comprehensive Review for Veterinary Technicians, 4th ed. p. 631. 41. How many permanent teeth are found in normal cats? 42 | 40 | 26 | 30 | 32 30 In cats there are 30 permanent teeth and 26 deciduous (baby) teeth. Ruminants have 32. Dogs have 42 permanent teeth. Food- loving pigs have the most teeth at 44. Horses vary between 36-44. Follow these links to see a diagram of normal cat dentition and a dental formula table for large and small animals. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1219. 42. Which is more severe, periodontitis or gingivitis? Depends on patient | No difference in severity | Periodontitis | Gingivitis Periodontitis Typically, peridontitis is a more chronic and severe problem. Periodontal disease is a general term that includes gingivitis (gum inflammation) and peridontitis (more chronic, severe damage from bacterial plaque that involves gingiva, periodontal ligament, alveolar bone, root cementum). Periodontal disease is caused by accumulation bacterial plaque at the gingival margin (gumline) due partly to lack of adequate oral hygiene. Follow these links to see: gingivitis in a dog, a radiograph of peridontitis with bone loss and Peridontitis in a dog. Refs: Tighe and Brown, Mosbys Comp review for vet techs , 3rd ed. p. 502, Bassert and Thomas, McCurnin’s Clinical Textbook for Veterinary Technicians, 8th ed. pp. 1321-2. 43. How many permanent teeth are found in normal dog? 44 | 42 | 32 | 30 | 24 42 Dogs have 42 permanent teeth. In cats there are 30 permanent teeth. Ruminants are in the middle between cats and dogs with 32. Food-loving pigs have the most teeth at 44. Horses vary by between 36-44. Follow these links to see a diagram of normal dog dentition and a dental formula table for large and small animals. Refs: Tighe and Brown, Mosby's Comprehensive Review for Veterinary Technicians, 4th ed. p. 631. 44. In which subpopulation of dogs is a metal crown most likely to be used to address repeated dental trauma? Working | Brachycephalics | Teacup breeds | Sight hounds | Emotional support Working Metal crowns may be placed on the teeth of working dogs who sustain repeated trauma (i.e., fractures) to their teeth.This allows them to continue doing their work. The teeth most often crowned are the canine and maxillary fourth premolar. Dr. John Lewis explains how these fractures can occur and how Crowns Can Be a Long Lasting Solution. Ref: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed. p. 1071. 45. The new owner of a small farm who has never owned livestock calls your office in distress. She says one of her calves is missing the upper front incisor teeth. Which choice is the best reply? This is normal | Might be a nutritional problem - need a vet visit and feed/forage analysis | This may be cleft palate - don’t breed until vet can examine | There may be fluoride toxicosis - need a vet visit and water analysis | Upper incisors do not appear until two years of age This is normal This is normal in ruminants. Cows and other ruminants do NOT HAVE UPPER INCISORS they have a thick dental pad, against which the lower incisors pull and cut forage. Chronic excessive ingestion of fluoride by cattle during the critical periods of tooth development, amelogenesis (enamel formation) and dentinogenesis (dentin formation) causes enamel hypoplasia, especially on the lower incisors. Follow this link to a ruminant dental formula from Merck. Follow this link to a Merck Manual tooth eruption table. Refs: Smith, Van Metre, and Pusterla's Large Animal Internal Medicine 6th ed. p. 805 and Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed. p. 190. 46. What structures make up the peridontium? Tooth root, cancellous bone of jaw, sinuses, branches of trigeminal nerve | Gums, tooth root cementum, periodontal ligament, alveolar bone of jaw | Cheeks, tongue, nasopharynx, soft palate | The part of the teeth below the gumline Gums, tooth root cementum, periodontal ligament, alveolar bone of jaw The peridontium is another name for all the structures that SUPPORT a tooth. These include the gums, the tooth root cementum, the periodontal ligament, and the alveolar bone of the jaw to which the ligaments attaches. Follow this link to see a tooth cross-section diagram. Refs:Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1227. 47. How are calculus-removing forceps different from extraction forceps? Different names for the same kind of instrument | Both ends are straight | Jaws lock | One tip is hooked, the other is straight | Spring-loaded handle One tip is hooked, the other is straight Calculus-removing forceps, used to crack off large chunks of calculus on teeth, have one tip that is hooked and one that is straight. This design makes for more effective manual calculus removal. An extraction forcep can have both tips straight or curved, and are available with and without spring-loaded handles. This article by Rebecca Hagney, VN goes into more depth on calculus-removing: Tools of the trade: Tartar Removing Forceps D1013 forceps. Ref: Tighe and Brown, Mosby's Comprehensive Review for Veterinary Technicians, 4th ed. p. 635. 48. What teeth are most commonly abscessed in dogs? Upper premolars | Lower wolf teeth | Upper canines | Lower incisors | Lower molars Upper premolars The most commonly abscessed teeth in dogs are the upper fourth premolars. These teeth are numbered 108/208 and is part of the carnassial teeth with the mandibular 1st molar. This Wikipedia post gives more information on the carnassial teeth. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1261. 49. As horses age, the occlusal surfaces of the incisors become more ____________ and the angle between the upper and lower incisors becomes ______________. Triangular, more acute | Triangular, less acute | Elliptical, closer to 90 degrees | Elliptical, less acute | Elliptical, more acute Triangular, more acute Triangular, more acute. When equine incisors first erupt, their occlusal surfaces are elliptical, then subsequently become trapezoid, round, and then triangular with the apex toward the lingual side. Click here to see the incisors of a 6 year-old horse. The angle between the upper and lower incisors also becomes more acute with age. Click here to see a diagram of equine dentition. Refs: Guide for Determining the Age of the Horse, American Association of Equine Practitioners, Lexington, KY, 2002. 50. Which part of a tooth is the occlusal surface? Towards the roof of the mouth | Above the gum line | Chewing surface | Toward the tongue | Toward the cheek Chewing surface The chewing surface of a tooth is occlusal. The crown is the visible tooth above the gum line. Buccal means the surface toward the cheek. Lingual is surface toward the tongue. Palatal is towards the roof of the mouth. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1220. 51. "Needle teeth" are sometimes nipped off in newborn pigs. Anatomically, what are the needle teeth? All the incisors | First and second premolars | Wolf teeth | Third incisors and canines | Canines and first premolars Third incisors and canines The needle teeth are the piglet’s deciduous third incisors and canines. Typically nipped to minimize teat trauma when piglets suckle the sow. Refs: Pasquini, Anat. Dom. Animals, 4th ed., p. 241 and the Pig Site. 52. After a routine spay, the vet asks you to clean up a cat's teeth, with special attention to tooth 304. Which tooth is that? Lower left incisor | Lower right premolar | Upper left canine | Lower left canine | Upper right canine Lower left canine Lower left canine. There are two slightly different tooth numbering systems, the anatomical and the Triadan systems, but they both number the canines and incisors the same way. This chart shows the modified Triadian numbering system in the dog. The upper right canine is 104. The lower right canine is 404. The upper left canine is 204. The lower left canine is 304. The first upper left premolar is 205. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1219-20. 53. Which choice is an exodontic procedure? Full mouth radiographs | Hand scaling | Tooth extraction | Soft tissue oral surgery | Mapping of the mouth Tooth extraction Exodontics refers to the extraction of diseased teeth. Endodontics, on the other hand, refers to root canal treatment to preserve a damaged or dead tooth. Based on the individual state's practice act, veterinary technicians may be allowed to perform certain non-invasive, non-surgical oral and dental procedures. Extractions are surgeries and can only be done by a licensed veterinarian. For more on dentistry, see the AVMA Veterinary Dental Policy. Ref: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed. p. 1217. 54. Which type of dentistry is a root canal procedure? Prophylactic | Dental equilibration | Endodontic | Cosmetic | Gingival Endodontic Endodontic procedures treat the inside of the tooth and the periapical tissues, including the tooth pulp and the tissues around the tooth tip and root. Root canals involve removing dead or dying tooth pulp and filling the canal to seal the tissue surrounding the tooth root. Only dogs and cats older than 12 months can undergo root canals because the root apex doesn’t close until 10-18 months of age and the root canal narrows due to dentin production as the animal ages. Dr. John Lewis gets to the bottom of Root Canal Therapy. Ref: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed. p. 1252. 55. What is the function of molar teeth? Nibbling | Holding | Grinding | Cutting | Shearing Grinding Molars grind food. Incisors are for cutting, nibbling food. Canines grip and tear food. The upper fourth premolar and lower first molar in carnivores are used to shear meat and are called the carnassial teeth. Refs: Tighe and Brown, Mosby's Comprehensive Review for Veterinary Technicians, 4th ed. p. 693. 56. What is the normal depth of the gingival sulcus in cats? 4-6 mm | 0.5-1 mm | 2-5 mm | 1-3 mm | 0 mm 0.5-1 mm Normal depth of the gingival sulcus in cats is less than 1 mm, in dogs 1-3 mm. The gingival sulcus is the crevice between the tooth and the gum line where plaque collects. It is important to know that this crevice is not very deep in normal cats when you are cleaning teeth. Dr. Jan Bellows explains the Role of Dental Probes and Explorers. Ref: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed. p. 1232. 57. Which choice is an endodontic procedure? Root canal | Radiation therapy for oral tumors | Tooth extraction | Full mouth radiographs | Soft tissue oral surgery Root canal Endodontics refers to root canal treatment to preserve a damaged or dead tooth. Root canal treatment on the canine teeth is the most common endodontic procedure in small animal medicine. After the procedure, these teeth are more brittle than normal teeth and may suffer fractures or breaks over time. Use annual radiographs to monitor the tooth condition after a root canal. Exodontics, on the other hand, refers to the extraction of diseased teeth. Based on the state's individual practice act, veterinary technicians may be allowed to perform certain non-invasive, non-surgical oral and dental procedures. Dental specialists usually perform root canals. For more on dentistry, see The AVMA Veterinary Dental Policy. Ref: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed. pp. 1217, 1252. 58. A five-year-old baboon is presented for an oral examination. If there is a problem here, what is it? This is normal in mature-adult primates | Gingival hyperplasia | Displacement and possible abscess of lower incisors | Fractured right lower canine tooth | Displacement and possible abscess of lower left canine (behind tubing) Gingival hyperplasia It does not matter that this is a baboon- this is gingival hyperplasia between the lower incisors. The treatment of choice is to remove the hyperplastic gingiva. Hyperplastic gingiva can be idiopathic or medication induced (cyclosporine, anticonvulsants). Refs: Veterinary Dentistry, Image courtesy, Dr Jan Bellows. 59. Using the Triadan system for numbering teeth, which quadrant of teeth is the 100-series? Left mandibular quadrant | This system is not used in veterinary medicine | Left maxillary quadrant | Right maxillary quadrant | Right mandibular quadrant Right maxillary quadrant The right maxillary quadrant is the 100-series, the left maxillary quadrant is the 200-series, the left mandibular quadrant is the 300-series, and the right mandibular quadrant is the 400-series. Click here to see the Triadan numbering system, which is used in veterinary medicine as a universal way to rapidly and consistently identify teeth in all species. Each tooth has a 3-digit number that starts at -01 increases as you move caudally. For example, the first right maxillary incisor is 101 and the left mandibular canine is 304. Here is a nice summary of basic dental topics courtesy of the Royal Veterinary College of London. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1219. 60. Which teeth are x-rayed using the parallel radiograph technique? Maxillary premolars | Mandibular canines | Maxillary incisors | Mandibular premolars | Mandibular incisors  Mandibular premolars Use the parallel radiograph technique for mandibular premolars and molars. Ref: Tighe and Brown, Mosby's Comprehensive Review for Veterinary Technicians, 4th ed. p. 729. 61. Which part of the tooth is considered to be living tissue? Enamel and dentin | Enamel and dura mater | Lignum and cementum | Dentin and pulp | Sulcus and periodontal ligament Dentin and pulp Dentin and pulp are living tissue. Dentin is formed by odontoblasts. Pulp is composed of odontoblasts and fibroblasts and is supplied by blood vessels, nerves and lymphatics. Enamel is acellular and considered nonliving tissue. Follow this link to see a tooth cross-section diagram. Refs: Tighe and Brown, Mosby's Comprehensive Review for Veterinary Technicians, 4th ed. p. 629 and Wikipedia Commons. 62. Which tooth is the first permanent molar to erupt in the horse's 100 arcade (as numbered by the modified Triadan system, this is the right upper arcade)? 105 | 106 | 109 | 107 | 103 109 According to the modified Triadan system, tooth 109 (first molar) erupts between 9-12 months and is the first permanent tooth to erupt in the 100 arcade. Tooth 105 (the wolf tooth) erupts sooner, but it is a premolar. 106-108 are premolars. Click here to see a diagram of equine dentition. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1264 and Guide for Determining the Age of the Horse, American Association of Equine Practitioners, Lexington, KY, 2002. 63. What is the correct description for the buccal side of a tooth? Faces tongue | Towards the roof of the mouth | Closest to gums | Grinding surface | Faces the cheek Faces the cheek The buccal side of the tooth faces the cheek. Lingual side faces the tongue. Labial surface of the tooth is nearest the lips. Gingival is the area of the tooth toward gums. Palatal is towards the roof of the mouth. Ref: Tighe and Brown, Mosby's Comprehensive Review for Veterinary Technicians, 4th ed. p. 631. 64. What kind of problem does a dog with mandibular brachygnathism have? Dangling participles | Undershot jaw with exaggerated incisor wear | Maxilla is longer than mandible | Polydontia | Mandible is torsed Maxilla is longer than mandible When the maxilla (upper jaw) is longer than mandible, you have mandibular brachygnathism. Another name would be overbite, or overshot jaw. Mandibular prognathism is an elongated lower jaw (think of a bulldog, for example). Polydontia is more teeth than normal. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1258. 65. What is the most common cause of lymphocytic-plasmacytic stomatitis in cats? Foreign body | Immune-mediated | Reaction to a drug | Viral exposure | Uremic toxicosis Immune-mediated Lymphocytic-plasmacytic stomatitis in cats is most often immune-mediated. Cats’ immune systems may over-react to plaque accumulation. While many cats with this disorder do shed herpesvirus and calicivirus, they are not thought to be causative. The other answers listed can cause stomatitis, but not as commonly. Therapy may include increased home care and frequent dental cleanings, immunosuppressive therapy, or full-mouth tooth extraction. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1263. 66. You are called to help examine a six-year-old Appaloosa gelding. The owner is worried because the horse seems sensitive and head-shy when he has a bit in his mouth. On physical exam you note a prominent pair of wolf teeth. What, anatomically, is an equine wolf tooth? Deciduous premolar 1 (Dp1) | Permanent incisor 3 (I3) | Permanent canine (C) | Deciduous canine (Dc) | Permanent premolar 1 (P1) Permanent premolar 1 (P1) Wolf teeth are permanent FIRST PREMOLARS (P1) seen in the upper arcade of 20-60% of horses. Wolf teeth (P1) are caniform (ie: canine-like) and erupt at around five to six months. Rarely occur in the lower arcade. Most horses that work with a bit in their mouth benefit from having the wolf teeth removed. Because the wolf-tooth looks like a little canine tooth, the first so- called "cheek tooth" in horses is actually the SECOND premolar (P2). Follow this link to a Merck Manual tooth eruption table. References vary by about six months, but here is a good rule of thumb for permanent tooth eruption in horses: I1-2.5 yr, I2-3.5 yr, I3-4.5 yr, C-4-5 yr. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed. p. 267 and Smith's Large An Med 3rd ed. pp. 601-05. 67. Which one of the following choices is the most common cause of enamel hypoplasia in cattle? Distemper virus | Hypermagnesemia | Fescue poisoning | Fluorosis | Copper toxicosis Fluorosis Fluorosis. Chronic excessive ingestion of fluoride by cattle during the critical periods of tooth development, amelogenesis (enamel formation) and dentinogenesis (dentin formation) causes enamel hypoplasia. Exposure to excessive fluoride after teeth are fully formed does not result in dental lesions. Dental fluorosis is commonly diagnosed by examining the incisiors, although all teeth may be affected. Dental lesions observed: staining, mottling, excessive erosion, hypoplasia, hypocalcification. Osteofluorosis and lameness may also be observed. Refs: Gibbons, Bov Med & SX, p. 288-300. 68. What kind of problem does a dog with mandibular prognathism have? Mandible is longer than maxilla | Irregular tooth wear causing wave mouth | Polydontia | Wry mouth | Deciduous teeth are retained in lower jaw Mandible is longer than maxilla When the mandible is longer than the maxilla, it is mandibular prognathism (projecting lower jaw--think of a bulldog, for example). When the maxilla (upper jaw) is longer than mandible, it is mandibular brachygnathism. Wry mouth is malocclusion when one segment of the jaw is disproportionately sized relative to the other half. Polydontia means having more teeth than normal. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1258. 69. What angle should be AVOIDED when using a magnetostrictive ultrasonic scaler to prevent tooth damage? Parallel | 45° | Tooth surface contact is important, not the angle | 90° | 180° 90° A magnetostrictive scaler can damage the tooth enamel if it is directed at a 90° angle (perpendicular to the tooth like a “T”) because the highest power dispersal is on the very tip. The back and the side surfaces of the scaler have the lowest power dispersal and are used most often for ultrasonic scaling. Ref: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed. p. 1240. 70. What do the blue arrows indicate in the lower incisors of this horse? Cups | Cavities | Equine odontoclastic tooth resorption and hypercementosis (EOTRH) | Galvanyne’s groove | Stars Stars The blue arrows indicate dental stars, composed of secondary dentin. The “***” and the “vvv” indicate dental cups, each of which is an infundibulum. Equine lower incisor teeth develop wear-related features that can be used to estimate age. The shape, position, and central “white spot” of the dental star changes with age as the tooth wears. The shape, size, and time of disappearance of the dental cups can be used but it is more variable. Click here to see a labeled image of a horse’s incisors at ages 6 and 12 years. There is a change in the occlusal shape of the incisors with age and wear (from elliptical to trapezoid, round, and then triangular). The angle between the upper and lower incisors becomes more acute (rather than being positioned in a straight line) with age. Galvayne’s groove is a dark line that appears at the gingival margin on the buccal surface of the third upper incisor (103 and 203) starting at ~10 years of age. It is often used to very roughly estimate age. Equine odontoclastic tooth resorption and hypercementosis (EOTRH) is a painful condition of the incisors characterized by dental resorption and excessive cementum production. Horses rarely get cavities, and even more rarely in the incisors. Refs: The Guide for Determining the Age of the Horse, Amer. Assoc. Eq Practitioners and the American College of Veterinary Surgeons, large animal health topics, Images courtesy of Uwe Gille and Nora Grenager, VMD, DACVIM. 71. The veterinarian diagnoses a dog with gingivitis. What is the problem? Irritated eyes | Tooth root infection | Epiglottal inflammation | Creeping eruptions | Inflamed gums Inflamed gums Gingivitis is inflammation of the gums. Look for reddening at the base of the teeth. Follow these links to see gingivitis in a dog. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 1236. 72. A two-month-old male mixed breed puppy is presented with a fever (104°F, 40°C [N=100.2–102.5°F; 37.9-39.2°C]), crusty oculonasal discharge, labored breathing, coughing, vomiting and diarrhea, anorexia, and lethargy. The presumptive diagnosis is canine distemper virus infection. What sequelae may be seen when permanent teeth come in? Gingival hypertrophy | Enamel hypoplasia | Retained deciduous teeth | Anodontia | Epulis formation Enamel hypoplasia Distemper causes enamel hypoplasia in permanent teeth if the dog is infected between two weeks and three months of age. Because distemper is a systemic disease, the entire dentition is affected. If infected between late-stage gestation and two weeks postpartum, only the deciduous teeth are affected. Dr. Brett Beckman discusses dental enamel defects in dogs. Refs: Cote, Clinical Veterinary Advisor: Dogs and Cats, 4th ed., pp. 271-3. 73. There are two types of ultrasonic dental scalers -- piezoelectric and magnetostrictive. What advantage does the magnetostrictive scaler offer over piezoelectric one? Produces more energy | Less fragile | Does not spray vaporized debris | Can be used as a separate hand scaler | Increased range of motion Less fragile Magnetostrictive transducers are less fragile than piezoelectric scalers because they are composed of thin metal strips as compared to a ceramic disc. A piezoelectric scaler can break if accidentally dropped. The magnetostrictive type of scaler is the most commonly used ultrasonic scaler in both veterinary and human dentistry. Ref: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed. pp. 1240-41. 74. Canine acanthomatous ameloblastoma is sometimes referred to by what general name? Odontogenic fibroma | Papilloma | Epulis | Odontoma | Malignant melanoma Epulis An acanthomatous ameloblastoma is also referred to as an epulis (plural = epulides), which is a general term for a gingival mass. It is an epithelial odontogenic tumor. Ameloblastomas often invade local tissues, including bone, but generally do not metastasize. Surgical excision is curative but must include one-cm margins of clinically normal tissue (including bone and teeth) to prevent recurrence. Often requires mandibulectomy/maxillectomy for definitive treatment. Radiation therapy is also effective, but can cause subsequent malignant tumor development in the irradiated area. Here is an image of an ameloblastoma, and a radiograph of an ameloblastoma. Px excellent if complete excision. Recurrence likely if margins are not clean. Peripheral odontogenic fibroma (previously fibrous epulis) is the most common canine benign oral tumor. They are typically slow growing and arise from the periodontal ligament. Surgical excision is typically curative. Refs: Cote, Clinical Veterinary Advisor: Dogs and Cats, 4th ed., pp. 306-9. 75. What is wrong with this rabbit? Click here to see image Click here to see image Diet too high in roughage | Malocclusion | Chronic calcium-phosphorus imbalance | Broken mandible, poorly healed | Oral damage from excessive cage chewing Malocclusion This is malocclusion of the incisors and they need to be carefully trimmed under anesthesia. Malocclusion is a common problem in animals whose teeth grow continuously throughout life, like rabbits and small rodents. Dental trimming in rabbits is done under anesthesia with bone or wire cutters, or with a grinding tool or dental burr (safer). Dental trimming in small rodents like mice, hamsters and gerbils can often be done with nail clippers or small scissors. Refs: Bassert, Beal and Samples, McCurnin's Clinical Textbook for Veterinary Technicians, 9th ed., p. 788 and Quesenberry and Carpenter, Clin Med and Surg of Ferrets, Rabbits and Rodents, 3rd ed. pp. 457-59.