What is special about rabbit’s teeth?
The layout of a rabbit's teeth is unique, and similar only to other lagomorphs such as hares. Rabbits have 28 teeth and these are usually divided into two groups: the incisors and the cheek teeth. The cheek teeth are often called premolars and molars, although there are no differences between these teeth in rabbits as there are in humans. The back teeth are used for grinding and the front incisors used for cutting and slicing through vegetation, although they can be used for gnawing and biting. They don't have canine teeth as they don't need to kill things to eat.
The upper molars slightly overlap the lower molars. Rabbits (and lagomorphs in general) have a single pair of large bottom incisors. The upper incisors include a similar pair of large or primary incisors and a pair of much smaller secondary incisors or "pet teeth" located directly behind the primaries. Normally, when the mouth is closed, the lower incisors slot between the upper ones and the peg teeth. The teeth rub against each other, keeping their cutting edges sharp for grazing. The food is then moved backwards to the molars for grinding and chewing.
Rabbit's teeth do not have real roots like dogs'. cats' or humans' teeth have, but their apex is often referred to as root. In fact, all their teeth grow continuously throughout the rabbit's life as they are constantly worn down when chewing on the tough grass and plants that they live on. These grasses and plants are very abrasive to their teeth. The duration of grazing and abrasiveness of the diet are both important factors that allow sufficient dental wear.
What goes wrong with rabbit's teeth?
So that this system can work appropriately, the teeth need to meet properly. If they don't, the resulting condition is often known as ‘malocclusion’.
This may occur from birth, because of the shape of some rabbits heads. Breeds with shorter noses such as the Netherland dwarf and Lionhead breeds may have crowded teeth. Rabbits can also get malocclusion from not getting enough fibre to chew to wear down their teeth as they grow. This is preventable by correct feeding.
Over grown teeth lead to all sorts of trouble for rabbits
Rabbit’s teeth grow at an astonishing rate. The incisors can grow as fast as 2-2.4mm per week, which is two to four times faster than the cheek teeth! They never stop growing and are worn down by the action of chewing. If things go wrong and rabbits develop dental changes, the resulting teeth malocclusion (dental disease) may cause, especially if left untreated, the following issues:
The molars will develop spiky bits on the outer edge of the top teeth and the inner edge of the bottom teeth. These spurs will dig into the cheeks and the tongue, causing salivation, pain and ulceration.
The bottom cheek teeth can overgrow, become misshapen and distorted and even penetrate the jawbone. This may result in pain and in some cases, infections.
Infections will ultimately lead to large swellings on the jaw line known as abscesses. These can be as big as golf balls and are filled with solid white pus.
The upper molars and/or incisors can also become overlong and can push upwards onto the tear duct of the eyes. This is the drainage channel of the tears from the eye, and if it is squashed by tooth roots, then the tears will overflow onto the fur surrounding the eye instead. This very easily leads to nasty eye infections. Rabbits can even get abscesses behind their eyes as a result of dental problems.
General ill health
If a rabbit is in pain, they will often stop eating. In turn, this will affect its general health, its digestion and the production of normal faeces. This situation may be life threatening and the development and progression of dental disease in rabbits can be fatal without treatment.
Symptoms to look out for, which may indicate dental problems
- Loss of appetite
- Loss of weight
- Dribbling or wet around mouth and chin
- Watery eyes, discharge or infection.
- A dirty bottom - due to not cleaning themselves.
- Lumps or bumps on the lower jaw.
- Any general ill health.
Prevention of dental disease due to insufficient wear can be achieved by feeding the rabbit a diet sufficiently high in fibres.
If you notice any of the above, do contact our veterinary team who will be happy to give you advice about what to do next.