Oral Cavity, Developmental Anomalies, & Teeth Flashcards
What is included in the postmortem exam of the oral cavity and the esophagus?
- conduct external exam of lips & muzzle
- split the mandibular symphysis & remove the tongue, hyoid bones, larynx, trachea, & esophagus via ventral midline skin incision
- expose & examine buccal cavities, dental arcades, palate, pharynx, including retropharyngeal lymph nodes, tonsils, & tongue
- open the entire esophagus & the mucosa & tunica muscularis
What is a physiologically normal oral mucosa?
smooth, shiny, pink (if not pigmented)
What lines the oral cavity?
stratified squamous epithelium (mucous mbs)
What are developmental anomalies of the oral cavity?
- palatoschisis (cleft palate)
- brachygnathia superior (short maxillae)
- brachygnathia inferior (short mandibiles)
- prognathism (long mandible)
- agnathia (absence of mandible)
- epitheliogenesis imperfecta (absence of epithelium of oral cavity &/or skin)
What is cheiloschisis?
cleft lip or hare lip
what is the most common developmental anomaly of the oral cavity?
palatochisis
what is the etiology of palatoschisis?
genetic or toxic
what is the pathology of palatoschisis?
failure of fusion of the frontonasal and maxillary plates
What are important clinical sequelae to palatoschisis?
- starvation (inability to suck)
- nasal regurgitation
- aspiration pneumonia
What is the etiology of palatoschisis in dogs?
- genetic abnormalities (ethical concerns whether to correct surgically such defects w/o also sterilizing the dog)
- associated w/ excessive intake of vitamin A during gestation
- administration of cortisone during gestation
Palatoschisis (cleft palate)
brachygnathia superior
prognathia
Epitheliogenesis imperfecta
- we euth these animals, in humans there are attempts to correct
epitheliogenesis imperfecta
what are the different types of dental disease?
- dental dysgenesis (odontogenic cysts)
- enamel hypoplasia
- abnormalities of wear
What are brachydont teeth?
- in carnivores
- do not continue to grow after they are fully erupted
- consist of crown, neck, root, enamel covering crown, cementum covering root
What are hypsodont teeth?
- in Eq & Ru
- have elongated body covered by enamel & cementum & continue to grow throughout life
- the cementum & enamel invaginate into the dentin, forming the infundibulum
What is an anomaly of tooth development?
segmental enamel hypoplasia
What is the pathology & etiology of segmental enamel hypoplasia in dogs?
- postnatal infection w/ canine distemper virus
- damage to ameloblasts (cells that produce enamel) of permanent teeth before eruption will result in segmental enamel hypoplasia
- after the virus is cleared, structure & function of the enamel organ return to normal
- thus, segmental enamel hypoplasia results from the lack of enamel formation during the period of virus infection
What is the pathology & etiology of segmental enamel hypoplasia in calves?
- hypoplasia of enamel of deciduous teeth sometimes caused by in utero infection with BVD
- after the virus is cleared, structure & function of the enamel organ return to normal
- thus, segmental enamel hypoplasia results from the lack of enamel formation during the period of virus infection
Who are abnormalities of wear most common in?
herbivores
what do abnormalities of wear result from?
- congenital or acquired irregularities in dental arcade or interference w/ mastication: protrusion of tooth, unilateral failure to wear
What is dental attrition?
dental wear that results in improper mastication & malnutrition (“step-mouth” or “broken mouth”)
What is malocclusion?
- failure of the upper jaw & lower incisors to oppose properly & it results from abnormal jaw conformation or rarely from abnormal tooth eruption patterns
- this is “normal” in some dogs (brachycephalic breeds)
what happens if rodents & rabbits are not provided w/ sufficient roughage in their diets?
teeth (both incisors & cheek teeth) overgrow &”lock” the jaw
What may explain emaciation or cachexia?
abnormalities of wear of teeth
What is important about wear in hypsodont teeth?
- in Eq & Ru cheek teeth
- continue to grow throughout life
- appropriate leveling of the occlusive surfaces (floating) may be a necessary procedure to prevent malocclusion & sharp edges that can lacerate the adjacent buccal mucosa as the Eq ages
What can exposure of dentin or the pulp canal lead to in all spp?
dental infection w/ serious consequences
What are caries?
- microbial destruction or necrosis of teeth
- damaged enamel cannot be regenerated or repaired
Who gets caries?
- domestic animal spp seldom get caries
- in Eq & Ru: it is the most common consequence of infundibular impaction & infundibular necrosis (usually in cheek teeth)
what can caries &/or periodontitis lead to?
tooth abscesses
What is dental plaque?
non-calcified accumulation of mainly microorganisms & their products that adheres to the teeth
what is dental calculus (tartar)?
calcified plaque deposits formed around the teeth
- may appear as supragingival or sub gingival calculus
What does the buildup of dental plaques and tartar predispose to?
caries, gingivitis, paradental stomatitis & periodontal diseases, & tooth loss
What happens along w/ gingival recession in brachydont animals?
- tooth root is not covered by enamel
- receding gum line exposes dentin, resulting in pain & invasion by bacteria
What is periodontal disease?
- dental plaque & tartar (calculus) predispose to gingivitis & gingival recession w/ ultimate loss of the periodontal ligament & alveolar bone & eventual loosening & loss of the tooth
What can the spread of the infection during periodontal disease result in?
causes alveolar osteomyelitis & pulpitis & can result in apical abscesses & bacteremia
what are the symptoms of periodontal disease?
- significant oral pain, reluctance to masticate & halitosis
Who gets periodontal disease?
- common in carnivores & humans
- affects most domestic mammals
how do you prevent periodontal disease?
- mildly abrasive diets & brushing of the teeth of pet carnivores
- combined w/ regular dental exams
Dentigerous cyst
enamel hypoplasia in young dog
enamel hypoplasia in newborn calf
Dental attrition (“step-mouth” or “broken mouth”)
overgrown teeth/malocclusion
infundibular impaction leading to caries
Dental plaque or tartar
