The incisors of rabbits and rodents continue to grow throughout their lifetime. The constant gnawing that should normally occur continually wears the teeth down. If the top and bottom incisors do not oppose (meet correctly), however, one or more of the teeth may overgrow. If this occurs, the affected incisor will need to be trimmed.
In rabbits and many rodents, the cheek teeth (teeth toward the back of the mouth) also continue to grow throughout the life of the animal. A diet consisting of tough, fibrous roughage is necessary to wear down the teeth. 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 (often called "slobbers"), 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, the roots of overgrown teeth may also elongate. When this occurs the root continues to grow through the oral tissues and can cause swellings. If this occurs in the cheek teeth of the upper jaw, the root can grow to the point of affecting the sinuses or the eye. This can result in drainage from the nose, discharge from the eye, or watering or bulging of the eye. When root elongation occurs in the lower jaw, it usually results in a large firm swelling.
The incisors (front teeth) of rabbits and rodents can occasionally fracture. This most commonly results from the animal chewing on or getting his teeth caught in the metal of a cage. Radiographs (x-rays) may need to be taken to determine how much of the tooth is involved. If the pulp of the tooth is exposed, the condition can be very painful. If this occurs, a veterinary dentist can remove part of the pulp and a temporary cap can be placed on the tooth. Since incisors continue to grow, the tooth normally coming into contact with the broken tooth may overgrow, and may need to be trimmed periodically. If the root of the tooth was not affected, and infection does not occur, the broken incisor will usually regrow. Sometimes the regrowing tooth is deformed and will need to be trimmed regularly.
Cheek pouch disorders in hamsters
Hamsters have large cheek pouches in which they can temporarily store food. There are several disorders that can involve these pouches.
Everted cheek pouches: For unknown reasons, in some hamsters, the cheek pouches may evert (turn inside out). The pouch appears as a pink, moist mass coming out of the corner of the mouth. A veterinarian can anesthetize the hamster, return the pouch to its normal position, and then place a suture (stitch) to keep it in place. A small amount of scar tissue will build up around the suture. This will help to keep the pouch in place after the suture is removed in about 2 weeks.
Impacted cheek pouches: In some cases, food may become impacted (tightly wedged) in the cheek pouch. This will appear as a large persistent swelling of the cheek. Under anesthesia, a veterinarian can remove the impacted food and flush out the pouch. The area will be examined to determine the reason for the impaction (e.g., an overgrown tooth). If the area has become abraded, antibiotics may be prescribed.