Dental Disease in Rabbits

The rabbit's teeth grow continuously throughout life in order to cope with constantly grinding food. This applies to both incisors (front teeth) and molars and premolars (back teeth). The obvious sign of dental disease is of incisor overgrowth with front teeth curling or sticking out at angles. This has been referred to as a separate entity and there are rare cases where this is due to injury to the teeth or congenital jaw deformity. However, most cases represent molar overgrowth forcing the jaws apart and destroying normal incisor occlusion.

Molar overgrowth may also result in the formation of sharp spikes piercing the tongue (lower) or cheek (upper), thus causing painful ulcers stopping the animal from feeding, eating its caecotrophs or grooming. The importance of continual food intake in rabbits is central to health, while grooming is essential to prevent problems like fly strike. Thus well-functioning teeth are absolutely essential to a rabbit's continuing well-being.

Why, you might ask, do these teeth grow abnormally?

The two major reasons cited for the formation of these problems is dietary deficiency – lack of either fibre or calcium (or both) will results in failure to wear down teeth (fibre) or soft bones (calcium). The former will result in overlong teeth with impaction of the roots while the latter will allow these teeth to move in the sockets thus altering the way they meet and facilitating entry of bacteria. There may also be congenital problems with short-nosed breeds being predisposed due to overcrowding of teeth.

Rabbits have evolved to eat grass!  This will be fresh grass in summer and dried grass (hay) in winter. In addition they will eat weeds and opportunistically take fruit or roots as they find them.

Modern pelleted or “muesli”-type diets were originally developed for fast-growing short-lived production rabbits. They are high in protein and low in fibre and minerals. Naturally rabbits love them and can obtain their daily calories without much chewing. Even if you give hay and grass with these foods, selective feeding by the rabbit will ruin the diet.

"Modern pelleted or “muesli”-type diets were originally developed for fast-growing short-lived production rabbits. They are high in protein and low in fibre and minerals."

It is therefore important to give large quantities of hay, grass and dark green leaves (cabbage, dandelions, etc) and top-up with a commercial ration (pelleted diets are best as they have a higher fibre content). Only give more of the commercial ration when all of the previous amount has been consumed.

It is important to have regular dental checks. For healthy rabbits this can be once or twice a year at the time of vaccination. However, it should be much more frequent for those with dental disease.

Incisors are easily examined and malocclusion identified. Ridging of the teeth may be a sign of poor enamel production or root infection.

Molars are much more difficult to examine being positioned at the back of a long, dark mouth. Conscious examination with an otoscope allows visualisation of the front few teeth and large spikes but dental disease cannot be ruled out on this alone. If suspicious, the rabbit should be anaesthetised, metal gags placed to hold the mouth open and the teeth examined with the naked eye or an endoscope. In many cases the problems originate from the tooth roots and skull radiography is indicated in most, if not all cases of dental disease.

Treatment

It is important to realise that the vast majority of cases will not “get better”. Long-term management is essential and corrective dental work will usually need to be repeated every few months, though the interval between each treatment can be increased by improving diet and correct dental technique.

Incisors

It is important not to miss underlying molar problems and address these too. Where incisors are growing faster than molars they may need to be cut back. This can be done in the conscious or anaesthetised rabbit. Clippers should not be used as they may induce shattering of the teeth and exposure of the pulp. Instead dental burrs or diamond cutting discs should be used to cut the teeth. The latter should not be used without protective guards in place.

Molars

On no account should molar therapy be carried out in the conscious rabbit. It is impossible to see what is being done. Instead anaesthesia and special mouth gags enable correct visualisation of the molars. Spurs may then be removed with special molar cutters or ground down with a mechanical burr. Overgrown molars should be reduced to the correct length using burrs or clippers. Burrs cause less shattering of the teeth and pressure on the roots. However, care must be taken not to cause damage to the sensitive tissues of the mouth.