Diagnosing Dental Disease in Small Mammals: A Vet's Guide
Since dental health can be a serious issue that affects a pet’s ability to eat, it’s important to address dental disease when it arises—even in the smallest of patients, like small mammals or pocket pets. While these tiny mouths can be challenging to work with, it is possible to evaluate and treat dental issues in these species.
In recent articles, we’ve discussed dental care in rabbits and guinea pigs. Today, we’ll focus on small rodents such as hamsters, gerbils, mice, and rats.
Which Dental Issues Do Small Mammals Develop?
These species (gerbils, hamsters, mice, and rats) can develop incisor malocclusions, since their incisors are open-rooted and grow continuously.
Unlike rabbits and guinea pigs, these small rodents have closed-rooted molars that do not grow continuously. Fortunately, that means that dental issues of the cheek teeth, while possible, are much less common.
On the other hand, since their molars have fully developed roots and don’t continuously erupt, small rodents may develop periodontal disease secondary to plaque. They may also develop dental caries if fed a diet heavy in sugar, including excessive use of certain commercial rodent treats.
Other oral issues include trauma to the teeth or jaws, food impaction, abscesses and infections, or diseases such as neoplasia. In hamsters, cheek pouch eversions or impactions are especially common.
Normal Dentition in Small Mammals
Mice, rats, gerbils, and hamsters have the dental formula 2(I 1/1, C 0/0, P 0/0, M 3/3), for a total of 16 teeth, with a space called the diastema between the incisors and molars.
The mandibular incisors are about three times as long as the maxillary incisors. The enamel may be white to yellow or orange, depending on the species.
As mentioned above, their incisors grow continuously, while their molars do not.
This dentition is consistent with the lifestyle of these small exotic pets. Their diet primarily includes seeds, roots, tubers, and grains—so unlike rabbits and guinea pigs, they don’t ingest a lot of fiber to the point where they require continuously erupting cheek teeth.
Their incisors wear down due to gnawing and burrowing behaviors. Chewing aids—such as wooden blocks or cardboard that is free of print or dyes—can help promote this natural behavior and keep the incisors in good shape.
Diagnosing Dental Disease in Small Mammals
Symptoms may be subtle at first, and it is common for pet owners to miss disease until it becomes more advanced. Symptoms may include anorexia, any change in behavior (such as hiding or hunching if they are in pain), drooling, and swellings or changes to face symmetry.
Hamsters with cheek pouch impactions may present with swollen cheeks. Or the cheek pouches may be seen protruding from the mouth in the case of eversions.
It’s possible for a veterinarian to do an initial, cursory oral exam on an awake pet using an otoscopic cone, and to evaluate the incisors on an awake pet. This method may uncover obvious abnormalities. But it is likely to miss subtle changes and does not allow for a thorough oral exam.
Anesthesia or sedation are best, both for a full oral examination and for dental radiographs.
Additional tools for small rodents, such as mouth gags and cheek retractors, are needed to get the best view of the teeth and oral cavity. Magnification can also be very valuable.
A dental x-ray study is best performed using a dental x-ray unit, with the sensor placed extra-orally due to the small size of these patients. Mammography film can also be used, as it shows fine details.
Treating Dental Disease in Small Mammals
For incisor malocclusions, the goal is to restore the teeth to their normal length and function. An appropriate type of dental drill is recommended. Avoid nail trimmers, rongeurs, and other cutting tools as these carry a risk of fracturing the teeth during trimming.
Molars should NEVER be trimmed since they have true roots and don’t erupt continuously. However, these cheek teeth may require removal of tartar and treatment of periodontal disease or even extraction of severely diseased or abnormal teeth.
For hamsters with cheek pouch eversions, viable tissue should be put back into normal position and sutured to the cheek. With impactions, the pouch must be emptied out and rinsed with saline.
Antibiotics and pain medications should be prescribed as needed, depending on the pathology.
Any vet treating dental disease in small rodents must have the appropriate sizes and types of dental tools. It’s also possible to use a needle (18 to 25-gauge, depending on the size of the patient) as an elevator during extractions.
Appropriate training is also very important, to ensure these small patients receive the specialized care their need.
Due to their fast metabolism, nutritional support is usually needed until the animal is recovered and eating on its own.
Owner Education is Important
Many clients buy these small pets for their children and don’t necessarily interact with the pets on a daily basis or have a deep understanding of their husbandry needs.
Promoting regular checkups of these patients can help to catch issues early, as well as educate owners on husbandry and on how to tell if their pet is ill.
All of this can serve to better the health of these small rodents and help to catch dental disease or other health issues early, when treatment may be simpler and carry a better prognosis.
Written by: Dr. Tammy Powell, DVM