Dental Caries

Typical Signalment

Dental caries can occur in any breed or size of dog. Greater risk of the condition with salivary gland dysfunction or dehydration as well as with diets high in fermentable carbohyrates or simple sugars.

Description

Dental caries is a plaque-induced demineralization of the teeth caused by the action of cariogenic bacteria on fermentable carbohydrates. The acid which is produced demineralizes the enamel and dentine. Bacteria is then able to invade the dentine and dentainal tubules, undermining the enamel and eventually causing the collapse of the enamel and cavitation of the tooth. The occlusal surfaces of the molar teeth are partiularly prone to caries.

Dental caries is a multi-factorial disease which requires all four of the following:

• Susceptible tooth surfaces
• A fermentable carbohydrate source
• Cariogenic bacteria (ie. Streptococcus and Lactobacillus)
• Time

The occurance of dental caries is low in dogs when compared with humans. Several reasons for this have been proposed:

• Few cariogenic bacteria in the normal oral flora
• High salivary pH, acting to neutralize acid produced by the bacteria
• Canine tooth surfaces are not prone to food impaction
• Diets are normally low in fermentable carbohydrates
• Lower frequency of food intake compared with humans

Diagnosis

Clinical Signs

• dysphagia
• reluctance to eat
• tooth pain and thermal sensitivity
• excessive salivation
• pain on mastication
• lethargy
• weight loss

Diagnostic Imaging

Radiographs of the tooth may show a radiolucency within the tooth or below the occlusal surface. The extent of lesions may be underestimated as a 40% loss of mineral content is required before a radiolucency is seen on a radiograph. In addition this means that advanced lesions are also more difficult to interpret.