Dentistry (Pope) Flashcards
Define pedodontics
Conditions of the puppy and kitten
Define periodontics
Study and treatment of diseases affecting the supporting structures of the tooth
Define exodontics
Branch of dentistry that deals with tooth extraction
Define endodontics
Diagnosis and treatment of diseases that affect the tooth pulp and apical periodontal tissues
Define orthodontics
Guidance and correction of malocclusion of the juvenile teeth and adult tooth positioning
Define prosthodontics
Tooth surface restoration
What are the functions of the different teeth types (i.e. incisors, canines, premolars, molars, and carnassial teeth)?
- Incisors (I): prehensile, grooming, cutting
- Canines (C): tearing, slashing, holding prey
- Premolars (P): holding, carrying, grinding (limited)
- Molars (M): grinding
- Carnassial teeth: adapted for cutting and shearing tissue (overlapping edges)
How many teeth do dogs have and what is their dental formula?
42 teeth - Maxillary: 3 I, 1 C, 4 P, 2 M - Mandibular: 3 I, 1 C, 4 P, 3 M
How many teeth do cats have and what is their dental formula?
40 teeth
- Considered to have 3 maxillary premolars (numbered from 2-4 [X06, X07, X08]) and 1 molar (X09)
- Maxillary: 3 I, 1 C, 3 P, 1 M
- Mandibular: 3 I, 1 C, 2 P, 1 M
What are the carnassial teeth in all carnivores? (TQ)
4th maxillary premolar (108, 208) and 1st mandibular molar (309, 409)
What is the anatomical system of numbering/identifying teeth?
- Teeth labeled based on what they are (i.e. M = molar, I = incisor, etc.)
- Letters are uppercase (adult) or lowercase (deciduous)
- Number is placed to the R or L of the letter depending on the side of the mouth (superscript or subscript depending on location, i.e. subscript = maxilla)
Explain the Triadan system of numbering/identifying teeth.
Each tooth is assigned a 3 digit number
- First number = quadrant (R maxilla: Q1, L maxilla: Q2, etc.)
- If deciduous teeth, quadrants are 5, 6, 7, 8 (clockwise from R maxilla)
- Second and third number = individual tooth
Define vestibular
Facing lips or vestibule
- Labial: toward the “lips”
- Buccal: toward the “cheeks”
Define palatal
Toward the palate
Define lingual
toward the tongue
Define coronal
Toward the crown
Define apical
Toward the root or apex of the tooth
Define mesial
Toward midline (think rostral - except incisors)
Define distal
Away from midline (think caudal - except incisors)
Define line angles
“Corners” of the teeth
- Mesial-buccal
- Buccal-distal
- Distal-lingual (or palatal)
- Lingual (or palatal)-mesial
Define crown
Portion of the tooth above the gum line covered by enamel
Define neck
Narrowed area of the tooth located at the gum line where the enamel ends and the cementum begins
Define root
Portion below the gum line covered by cementum
Define apex
Most terminal portion of the root
Define apical delta
Very small openings found at the apex, which allow the nerves and vessels to enter the pulp cavity
Define enamel
Calcified organic matrix that covers the crown of the tooth
- Hardest substance in the body
- Formed prior to eruption
Define cementum
Bony tissue that covers the surface of the root
Define dentin
Dense bony-like matrix layer beneath the enamel and cementum
- Porous layer sensitive to heat or cold b/c dentinal tubules allow indirect access to the nerves in the pulp chamber
What’s the pulp cavity?
Contains nerves (sensory only) and vessels that comprise the “living” layer of the tooth
- Portion in the crown = pulp chamber
- Portion in root = root canal
What’s the periodontal ligament?
Connective tissue structure mainly composed of collagen fibers that are imbedded in the cementum and periosteum of the alveolar bone
What is alveolar bone?
Cancellous bone directly surrounding the tooth roots
Define periodontium.
Supporting structures of the tooth
- Periodontal ligament
- Gingiva
- Cementum
- Alveolar supporting bone
What’s the gingival sulcus?
Shallow groove between tooth and free gingiva
What’s the junctional epithelium?
Epithelial attachment of free gingiva to the root at the bottom of the sulcus - Important structure in preventing periodontitis development
According to AVDS, what is a stage?
Assessment of the extent of pathological lesions in the course of a disease that’s likely to be progressive (e.g. stages of periodontal disease, staging of oral tumors, etc.)
According to AVDS, what is a grade?
Quantitative assessment of the degree of severity of a disease or abnormal condition at the time of diagnosis, irrespective of whether the disease is progressive (e.g. grade 2 MCT)
According to AVDS, what is an index?
Quantitative expression of predefined diagnostic criteria where the presence and/or severity of a pathological condition is recorded by assessment a numerical value (e.g. gingival index, plaque index, etc.)
What percentage of dogs and cats with no clinical signs show important radiographic findings?
- Dogs: 30% - Cats: 40%
What percentage of dogs and cats with clinical signs show important radiographic findings?
50% or more
What are the indications for taking oral radiographs?
- Preventative dentistry (w/ teeth cleaning) - Pre- and POST-extraction - Stage 3 and 4 Periodontal disease - Fractured tooth - Idiopathic oral pain - Resorptive lesions - Missing teeth - Oral trauma - Endodontics
What’s the preferred method for dental radiography?
Intraoral techniques - Extraoral techniques using standard radiograph machines and film suitable for assessing entire skull, but don’t provide adequate detail for assessing dental problems
In dental radiographs with traditional intraoral film, there’s a dimple to establish orientation. What’s the rule about the dimple?
The dimple is always pointing up (pointing toward the tube head) and oriented toward the crown
Describe the parallel technique for intraoral radiographs and what teeth it’s used for (PTQ).
Used for the mandibular premolars and molars - X-ray beam placed at a right angle to the teeth and the film (end of x-ray cone parallel to tooth and film)
Describe the bisecting angle technique for intraoral radiographs and what teeth it’s used for.
Use for every other area of the mouth in dogs and cats besides the mandibular premolars and molars - X-ray beam placed at a right angle to the imaginary line bisecting the angle of the long axis of the tooth and the angle of the film
What are some complications when using the bisecting angle radiographic technique?
- Elongation: tooth appears longer (cone was aimed too directly at the subject - cone end more parallel to TOOTH) - Foreshortening: tooth appears shorter (cone aimed too directly at the film - cone end more parallel to FILM) - Overlapping: common problem when radiographing upper 4th premolar (palatal and mesial buccal roots often overlap)
What’s the SLOB rule?
Same Lingual Opposite Buccal - Used for radiographing the 4th premolar - The more palatal root will appear shadowed ont hef ilm in the SAME direction as the beam (tube head) moved and the more buccal root will be shadowing in the opposite direction that the beam moved
When does tooth development start and end?
- Starts in the fetus - Ends by 6th-7th mos. of life
Where do teeth arise from?
Both mesenchymal and epithelial precursors
When does tooth development start?
Starts when the dental lamina split for form separate buds (enamel organs) - Separate bud for deciduous and adult teeth (but the permanent bud arises from the deciduous bud in utero)
What is the complication with the permanent bud?
Arises from deciduous bud in utero - if there’s no deciduous tooth, there will be no corresponding permanent tooth
What are successional teeth?
Adult teeth preceded by a deciduous tooth - Most of the teeth
What are non-successional teeth?
Adult teeth with no deciduous counterpart - Molars, 1st premolar (dogs) - Molars (cats)
Describe diphyodonts.
Species with deciduous (primary) teeth following by adult (permanent) teeth
How is enamel formed?
Formed by ameloblasts found in inner lining of enamel organ - Formed before the tooth erupts and not replaced if damaged
How is dentin formed?
Formed by odontoblasts (outermost layer of mesnchymal dental papilla) - Continually produced throughout life of the tooth
When is primary dentin formed?
Formed while tooth is developing
What is secondary dentin and what does it cause?
Dentin formed after the tooth has erupted and the apex closes - Causes dentin widening as animal ages - Structurally similar to primary dentin
What happens to dentin due to attrition or abrasion?
- Wear occurs slowly → tertiary (reparative) dentin formed to prevent pulp exposure
What is tertiary dentin?
Structurally different dentin with a few tubules - Tubules help prevent bacteria from entering pulp cavity
What is the pulp and it’s characteristics?
Contains blood vessels, nerves, and connective tissue - Remains active throughout tooth life
What does the pulp do?
- Initially causes root lengthening (which causes eruption) - Closure of the apex - Continual narrowing as animal ages
When does apical closure of canine teeth occur?
About 18 mos. old
What happens to the pulp chamber and dentin with age?
The pulp canal becomes progressive small while the dentin thickens
When do the deciduous teeth erupt?
Erupt as the tooth lengthens
When does the deciduous tooth root undergo resorption?
Soon after the tooth is fully erupted
What also occurs during deciduous tooth resorption?
Permanent tooth bud starts its development and erupts as the deciduous tooth is shed
What are factors that influence eruption times?
- Sex (females earlier than males) - Breed size (larger breeds erupt earlier) - Birth season (animals born in summer erupt earlier) - Nutritional/health status
What are the eruption times for deciduous teeth in dogs?
- Incisors: 3-4 weeks - Canines: 3 weeks - Premolars: 4-12: weeks
What are the eruption times for deciduous teeth in cats?
- Incisors: 2-3 weeks - Canines: 3-4 weeks - Premolars: 3-6 weeks
What are the eruption times for permanent teeth in dogs?
- Incisors: 3-5 months - Canines: 4-6 months - Premolars: 4-6 months - Molars: 5-7 months
What are the eruption times for permanent teeth in cats?
- Incisors: 3-4 months - Canines: 4-5 months - Premolars: 4-6 months - Molars: 4-5 months
What are impacted or unerupted teeth?
Teeth that have not erupted during the normal time frame
What’s the most common impacted or unerupted tooth?
Mandibular 1st premolar
What breeds are predisposed to impacted (unerupted) teeth?
Brachycephalics (Boxers, Pugs, Shih Tzu, Boston Terrier)
What’s indicated/recommended for impacted (unerupted teeth)?
- Dental radiographs - Extraction recommended to elimiate risk of dentigerous cyst formation
When should occlusion be evaluated in puppies and kittens?
Early in life - If possible, interceptive orthodontics initiated if malocclusion present
What are the characteristics of normal occlusion?
Also known as scissor bite - Maxillary incisors close jut in front of (rostral to) mandibular incisors - Mandibular canine should interdigitate between maxillary lateral incisor and canine - Upper 4th premolar should close to the outside (buccal surface) of the lower 1st molar - Maxillary and mandibular premolars should interdigitate (create pinking shear appearance)
What are the classes of malocclusions?
- Class 1: Neutroclusion - Class 2: Mandibular distoclusion - Class 3: Mandibular mesioclusion - Class 4: Asymmetrical skeletal malocclusion
Describe a class 1 malocclusion.
Jaw normal length, individual tooth or teeth within segment affected
What are some examples of a class 1 malocclusion?
- Rostral or Anterior cross bite (1+ maxillary incisors displaced toward palate [caudal to mandibular incisors when mouth closed]) - Caudal or Posterior cross bite (maxillary premolars lingual to mandibular premolars or molars) - Base narrow canines (adult mandibular canines erupt lingually and may impact hard palate and cause oronasal fistula of not corrected) - Lance tooth (rostrally displaced adult canine tooth)
What is the most common class 1 malocclusion in dogs?
Base narrow canines
What breeds are Lance teeth most common in?
Most common in Sheltie - Also Schnauzer, Italian Greyhound, Fox Terrier
Describe a class 2 malocclusion.
Mandibular distoclusion
What is an example of a class 2 malocclusion?
Brachygnathism (upper jaw longer than the lower jaw) - Also called an overbite or parrot jaw
Describe a class 3 malocclusion.
Mandibular mesioclusion
What are some examples of a class 3 malocclusion?
- Prognathism (mandible longer than maxilla; also called underbite or monkey mouth) - Level bite (incisor crowns meet instead of mandibular incisors being directly behind the maxillary incisors)
What’s unique about prognathism and brachycephalic breeds?
Considered “normal” in brachycephalic breeds
What is another issue with a level bite?
Considered degree of prognathism - Causes attrition
Describe a class 4 malocclusion.
Asymmetrical skeletal malocclusion
What is an example of a class 4 malocclusion?
Wry mouth or Wry bite - Occurs due to elongation of 1/2 of head - Leads to unequal arch development - Oral exam shows midline of mandible and maxilla don’t line up - Can be acquired as a result of trauma to one side of the face or inherited
What is the primary goal when assessing and treating malocclusion?
Giving the patient a pain-free, functional mouth
What may be involved when major (very abnormal) malocclusions?
Certain teeth may need extraction or have their crown height reduced - Prevents trauma to other teeth and/or soft tissue structures in the mouth (alternative to orthodontic movement)
What’s interceptive orthodontics?
Enough primary teeth may be extracted to allow normal eruption of the adult tooth and/or prevent dental interlock so small differences in growth rates of the upper and lower jaw may correct over time - Benefit to early recognition of a major malocclusion
What can occur with retention of deciduous mandibular canine teeth?
Lingual eruption of adult canines (base narrow canines; most common class 1 malocclusion in dogs)
Define crowding.
Teeth are misaligned due to too many teeth (i.e. supernumerary teeth) or the jaw is too small for normal number of teeth - Teeth may be in normal location and rotated - May also be displaced from their position in the dental arch
What can crowding cause?
Malocclusion and/or attrition due to: - Abnormal tooth contact - Predispose to periodontal disease
What is oligodontia and its degrees (anodontia/hypodontia)?
Genetic defect with premolars most commonly affected “Missing teeth” can range from: - One or two (hypodontia - Entire mouth (anodontia
What breeds are predisposed to oligodontia?
Mexican Hairless, Chinese Crested Dogs
What’s the problem with retained deciduous teeth?
Can cause displacement of permanent teeth - Can lead to orthodontic problems or soft tissue trauma - Also create good place for periodontal disease development
What’s the rule of dental succession?
No deciduous and permanent tooth should be in competition for the same space at any time
Where do permanent teeth erupt to in relation to deciduous teeth?
Usually erupt lingual to the deciduous teeth - Exception: maxillary canine (erupts rostral [mesial] to deciduous canine)
What’s the treatment for retained deciduous teeth?
Extraction
What is tetracycline staining?
Tetracycline given to pregnant bitches and queens in the last 2-3 weeks of gestation (or given to young pups/kittens when adult teeth are developing) leads to yellow-stained teeth
What’s the primary layer affected with tetracycline staining?
Dentin
What’s the treatment for tetracycline staining?
No treatment
What occurs with enamel hypocalcification?
Enamel matrix is formed properly but mineralized affected - Often causes wavy, somewhat translucent appearance in enamel
When does enamel hypoplasia occur?
When there’s damage to the ameloblasts during enamel development - Matrix isn’t produced appropriately
What are the effects on permanent tooth development from Distemper virus infection?
Generalized or focal enamel defects that lead to a worn down tooth with an irregular knob shape over time - Exposed dentin “porous” and stains easily → yellowish-brown color tooth/teeth - Can be another disease process that causes high fever - In some, like Tibetan Terrier, root abnormalities occur along with the enamel effects
What’s the treatment for teeth affected by Distemper virus infection?
If focal, can restore defect w/: - Composite - Crown (cap) important teeth to prevent wear If generalized defects: - Good home care - Frequent cleanings
Define attrition.
Wearing away of the crown by tooth against tooth contact
What is the etiology for attrition?
Malocclusions
What are the treatments for attrition?
- Early orthodontic correction - Monitor for pulp exposures - If mild, crown reduction (may also need endodontic treatment) or extraction(s) to relieve contact
Define abrasion.
Wearing away of the crown by abnormal contact w/ structures other than the teeth
What is the etiology of abrasion?
Cage biters, tennis balls, rocks, sticks, etc.
How do you treat abrasion?
- Remove causative agents from environment - Monitor teeth for pulp exposure and crown fractures (extraction usually most practical in these cases)
What is enamel abfraction, what teeth are usually affected, and what do these teeth look like?
Also called infraction or craze lines
- Due to heavy chewing, etc.
- Resulting flexing of teeth cause enamel microfractures
- Canine teeth commonly affected
- Teeth staining often occurs in concentric lines mainly on distal (caudal) tooth surface
What are dental caries, and what is their incidence in dogs and cats?
Focal demineralization and loss of tooth structure
- True incidence unknown but genreally less common than people
- Probably due to scissor bite, conical crowns, higher salivary pH, and a diet lower in germentable carbohydrates
What’s the etiology of dental caries?
Occur when plaque with bacteria has access to fermentable carbohydrates
- Bacteria produce organic acids (metabolism by-products)
- Acids dissolve minerals in the enamel
- Results in tooth surface breakdown
What are the most common locations of dental caries?
Most commonly
- Maxillary 1st and 2nd molar OR
- Mandibular 1st molar
- Teeth w/ flat surfaces and pits or fissures on tooth surface
What do dental caries look like?
Decayed dentin: brownish in color with a soft leathery feel that catches the dental explorer as its drawn across the surface
- Looks like healthy dentin when the enamel covering has been disrupted
How are dental caries commonly treated?
Depends on stage and location
- If not penetrating pulp cavity = indirect pulp capping
- Penetrating pulp cavity = direct pulp capping IF pulp vital
- Endodontic involvement = root canal
What should be considered with extensive dental caries or lesions?
Extraction
- Most often the case
What is the etiology of gingival hyperplasia?
Periodontal disease or other inflammatory processes
What breeds often show signs of generalized gingival hyperplasia, and what’s the etiology?
- Most often seen in Boxers, but also common in Great Danes
- Unknown cause but can occur w/ drug admnistration (cyclosprine, calcium channel blockers, some anticonvulsants)
what are some treatment options for gingival hyperplasia?
- Discontinue mediciation, if possible
- Gingivectomy/gingivoplasty
How do you perform a gingivectomy/gingivoplasty?
- Sulcus (pseudo-pocket) depth measured and marked on gingival surface
- Using a radiosurgical blade or loop, exicse the gingiva by cytting below the points made by the probe with the blade at a 45o angle with the tip of the blade toward the crown
- Incisions should taper into surrounding gingiva to create normal scalloped contour
- Radiosurgery reduces blood loss but caution w/ thermal damage
What is the after-care for a gingivectomy/gingivoplasty?
- Analgesics
- BID rinses w/ 0.12% chlorohex solution for 2 wks
- Re-examine in 2-3 weeks
- Continue home care and dental cleanings
What can help reduce comfort in gingivectomy/gingivoplasty?
Decaffeinated tea rinses
What are the etiologies of crown fractures?
Usually due to force exterted when chewing on inappropriate items
What is the most commonly fractured tooth?
Upper 4th premolar (108, 208)
- Canine teeth also commonly fractured (esp. in dogs trained to bite or catch hard objects)
What type of fractures can result from chewing on hard objects (specific type of crown fracture)?
Chewing on hard objects (i.e. very hard chew toys) can cause shearing fractures (slab fractures) that may extend onto the surface of the root
What are the clinical signs of crown fractures?
RARELY PRESENT D/T O NOTICING FRACTURE
- Often found when tartar removed during dental OR dog presents w/ swelling below eye
- May notice change in eating habits
- O may note canine teeth fractures at injury or may present later w/ unilateral nasal discharge or mandibular swelling
In crown fractures, what creates the swelling below the eye?
Endodonctic granuloma/abscess that forms at the apial area
How are crown fractures classified?
- Fracture location
- Portion of tooth involved
- Pulp exposure (present/not present)
- Uncomplicated: no pulp exposure
- Complicated: pulp exposure
What’s important about complicated crown fractures?
Pulp injury must be addressed as well as injury hard tissue injury to enamel and dentin by either:
- Vital pulpotomy
- Root canal
- Tooth extraction
What are the treatment options for crown fractures?
- Tooth extraction ± antibiotics
- If minimal periodontal involvment, tooth can be saved by performing vital pulpotomy or root canal
How do endodontic lesions recognized?
Usually recognized by crown discoloration due to RBCs entering the dentinal tubule and pulp ultimately dies (in most instances)
What is the etiology of endodontic lesions?
Usually due to exposure of the pulp chamber through:
- Crown fracture
- Abrasion
- Peridontal lesions
- Caries
- Resorptive processes
- Traumatic processes
What happens if (when) the pulp cavity becomes infected?
Endocontic abscess (periapical granuloma) will form at the apical end and can progress to
- Draining tract
- May remain sub-clinical for a time
What is a parulis and where does it occur?
Draining tract occuring the mouth
- Usually at or apical to the mucogingival line when assoicated w/ periapical inflammation due to endodontic disease
How do you treat endodontic lesions?
Extraction or endodontic therapy (root canal)
- Antibiotic treatment may be indicated with periapical disease
- Successful root canal = MOST IMPORTANT STEP if want to maintain tooth
What should happen to teeth with combined periodontal and endodontal lesions?
Extract the tooth
What are the rules to remember with acute pulp cavity exposure?
- If animal is < 18 mos., and fracture < 2 weeks old (< 48 hours better) = could consider vital pulpotomy w/ direct pulp capping (present continued pulp chamber development)
- Success goes down the longer the pulp is exposed
