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 25-28 September, 2018 | Singapore
monitored for all species. Dental disease may result in concurrent gastrointestinal stasis due to excessive fur chewing/self-grooming, poor appetite, pain and lack of dietary fibre.
Dental disease in rabbits
There are three main causes proposed for acquired dental disease (ADD) in rabbits: 1) congenital factors (mandibular prognathism, malocclusion), 2) nutritional (reduced fiber intake) or 3) metabolic bone disease (reduced sunlight exposure causing lower calcium levels and higher PTH) These factors may result in improper or insufficient wearing of incisor and/or
cheek teeth (CT) as well as formation of periapical abscessations and osteomyelitis. Staging of dental disease in rabbits is performed commonly by performing extra oral radiography and endoscopy. In early stages, mild or absent clinical signs may be seen. However radiographically, elongation of CT crowns is present with slight curving of first premolars. There is slight deformation in the ventral mandibular cortex and interproximal space of mandibular CT may begin to widen. The incisor teeth usually appear normal. In
the later stages, the occlusal surface of the CT will
be abnormal (“wave mouth”) and excessive CT crown elongation and differences in crown height is present (“step mouth”), curvature and deformation of the mandibular or maxillary CT roots may occur, ventral mandibular cortical deformity will become more obvious, eventual root perforation of CT1 and CT2 into cortical bone will occur, fractures of elongated CT frequently occur, abnormal curving and malocclusion of incisor teeth is present. In the late stages, an endoscopic oral exam will reveal excessive crown elongation, deviation of CT and spurs may be seen as well as resulting ulcerations. In the end stages, radiographically there
is radiolucency of the mandible, compensatory bony calcifications of the mandible, general lack of normal
CT anatomy and incisors and clinical crowns are non- growing/absent or fractured.
Other diagnostic modalities
Intraoral dental radiographic techniques have been described for rabbits and are advocated to allow early detection of lagomorph dental pathology. This technique can be performed in conjunction with extraoral views to aid in visualization and guide veterinarians in providing proper treatment and prognosis.
Computed tomography scans (CT scans) should be considered for advanced to late stages of dental disease to provided more details about the extent of the dental pathology, which is likely to be important for establishing a more precise prognosis and treatment plan for the patient.
Malocclusion of incisor teeth is less frequent but when seen is typically secondary to CT disease. Hence,
they serve as excellent indicators of CT abnormalities. Excessive CT elongation and malocclusion is likely due to poor nutrition causing improper wear. Radiographically, malocclusion and elongation of the incisors may be apparent, deformities of the cortical bone may be seen but are subtler than in rabbits. These lesions are usually more painful in guinea pigs and may not be relieved by coronal reduction. On endoscopic exam, the occlusal angle is sloped more than the normal 45 degree angle from buccal to lingual in severe cases of malocclusion. There will be crown elongation and malocclusion of CT and one or both mandibular CT1 is commonly affected in early stages. This may cause entrapment and discomfort of the tongue. Food and hair impaction is very common. Buccal spurs of maxillary CT may also cause ulcerations.
Dental disease in chinchillas
Malocclusion of incisors are not frequently encountered and usually secondary to dental disease of the
cheek teeth. Traumatic fractures of incisors may be encountered and may result in long term overgrowth and deviation. Crown elongation and malocclusion is caused by abnormal wear due to poor nutrition. Radiographically the occlusal surface is uneven, elongation of CT
crowns with CT 1 being most commonly elongated in early stages, partial resorption and abnormal curvature of CT may occur and in later stages deformity of the ventral cortical bone is seen with wider interproximal spaces. Malocclusion and elongation of incisors and completely abnormal occlusal surfaces are also common in late stages. Endoscopic exam will reveal excessive elongation of crowns with increased alveolar crest and gingival margins and molar spurs. Proliferation of gingiva may also be present and are usually associated with pain and poorer prognosis. There is excessive wear and even absence of clinical CT crowns in end stage disease.
Dental procedures
Specialised dental equipment such as cheek dilators, mouth gags, rodent table restrainer, periodontal
probe, high speed dental handpiece or Dremel and appropriate burs, molar cutters, Crossley’s luxators for cheek teeth and incisors, small curved hemotstat and extraction forceps are necessary for the successful dental procedures which may include coronal height reduction, dental extractions, and incisor trimmings. Surgical magnification and light sources are also highly recommended to allow better visualization of the inner oral cavity. The patient should be deeply anesthetized for all dental procedures to prevent accidental trauma due to head and tongue movements. The soft tissue such as the tongue or buccal mucosa should be shielded using an instrument such as a spatula. Moistened cotton tip applicators can be used to periodically clean the working surface of the teeth and remove tooth dust. Spikes and
Dental disease in guinea pigs

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