Dental Anatomy and physiology amongst small mammals differ considerably. Knowing these differences is important for proper diagnoses and treatment. Among the more important differences are the overall numbers of teeth and their patterns of growth. In some small mammals, dental disease is most commonly secondary to dental disease of the cheek teeth which is usually due to improper wear. In other pets, it is usually related to trauma, often secondary to chewing on cage enclosures or attempting to eat inappropritely large food items. If their teeth grow continuously, it may be necessary to trim their incisors.

We recommend general exams twice a year for all exotic pets. 

Rabbits

Rabbits are diphyodont, having two recognizable sets of teeth. Larger teeth replace the set of smaller teeth they have when they are young, usually by day 35. Rabbits and rodents lack canine teeth. Their permanent teeth grow and erupt continuously. The cheek teeth of rabbits grow and erupt at approximately 3 to 4 mm per month. Maxillary teeth grow and erupt at a slightly slower rate. A long gap exists between the incisors and premolars in both rabbits and rodents. The cheeks fold in behind the incisors separating the front of the oral cavity from the more caudal section, thereby permitting separate function of the incisors and back teeth. When a tooth is lost or extracted, it can leave gaps where food can get stuck. Periodontal disease can become a problem, so appropriate dental care is very important.

Rodents

Most species are considered monophyodont meaning they have a single set of teeth without precursors or successors. They have teeth with a long continuously growing crown and no anatomical root. This compensates for the constant wear that occurs when eating their natural diets. Most  rodent incisors contain a yellow-orange Iron based pigment that Guinea Pigs do not have. Like in rabbits, a gap sits between the incisors and molar teeth. 

Rats, Mice and Hamsters

These small animals feed mostly on seeds, grains and tubers. These are high-energy foods with minimal abrasive properties that require little chewing so the cheek teeth are subjected to minimal wear. This results in them not needing constant replacement. They have short crowned molars which have anatomical roots that stop growing once they have erupted. Their incisors also contain a yellow-orange enamel and may be used for biting, but have evolved for gnawing using a forward scraping action of the lower teeth.

Dental and Oral Care

In the truly herbivorous pocket pets, a diet consisting of tough, fibrous roughage is extremely important to the health of the animal. If a diet that does not require enough chewing is given, cheek tooth wear is uneven causing spikes of enamel to grow on the outer and inner sides of the teeth. These spikes can cause severe oral pain resulting in excessive salivation, reluctance to chew, inability to close the mouth, and reduced food intake. The situation deteriorates as the teeth continue to grow, and, if it is not treated, will result in severe malnutrition.

In some species, cheek tooth overgrowth can lead to root elongation. When this occurs the root continues to grow through the oral tissues causing swelling. If this occurs in the upper jaw, the root can grow to the point of affecting the eyes, resulting in watering, bulging, or inflammation.

The teeth should be examined routinely for abnormalities and a balanced diet enriched with coarse vegetation should be fed to maintain adequate wear. If diagnosed early, the enamel points and/or overgrown incisors can be trimmed. In more severe cases, permanent damage may have already occurred.

It is important to know, especially in the differing rodents, the anatomy and physiology of the teeth so appropriate care and nutrition can be provided for a long and healthy life.