Rabbit dentistry is a complex subject. There's so much still to learn, with ideas changing virtually from month to month, that it's easy to forget how far things have come compared to ten years ago….. in the early 1990s, euthanasia was the primary "treatment" of most rabbit dental problems.
The RWA|F Rabbit Health Liaison team are currently preparing a detailed guide to rabbit dental problems, designed specifically for rabbit owners. When this work is complete we hope to publish it in paper format as well as here on the website.
Hence, the information below is a temporary addition to the RWF website and it will be replaced by a far larger section (hopefully illustrated) sometime in the next few months.
The article below first appeared in the Winter 1998 issue of Rabbiting On, but was updated in March 2002.
A toothy problem?
Rabbit dentistry is a huge topic, and the full story hasn’t yet been unravelled. There are conflicting theories as to what goes wrong with rabbit teeth. What we present here is inevitably a mix of these theories.
What’s meant to happen?
Rabbit teeth are amazing. The front teeth are only a small part of the story. It’s the molars, hidden away at the back of the mouth, that do most of the work - and cause most of the problems.
If you look in the mouth of an old horse, you’ll find the teeth are all worn down. That’s because grass is very abrasive. Rabbits eat grass too, but their teeth grow continuously and rapidly enough to ensure there is always a fresh new tooth surface to grind food efficiently. Watch a rabbit chewing hay: you’ll see the jaw moving from side to side. It’s this crucial chewing action which, together with the right diet, keeps the back teeth the correct length.
So, what goes wrong?
If the teeth aren’t worn down properly by chewing abrasive plants (grass) the teeth crowns grow too long. As a result the correct chewing motion is lost. Next, the top and bottom teeth start pressing together when the mouth is closed and the teeth can no longer erupt upwards. Instead, they grow backwards into the jaw. It’s these overgrown tooth roots projecting into the jaws and skull that cause so many problems for our rabbits.
I keep reading about calcium, diet and teeth problems. Where does calcium deficiency fit into all this?
It’s a very good question - even the leading authorities don’t agree where calcium deficiency fits into the picture! However, correct diet unquestionably plays a crucial role in rabbit dental health. Most British pet bunnies are calcium deficient from poor diet and lack of sunlight and have some degree of dental disease.
Beyond that there is controversy. One theory is that calcium deficiency is the primary problem - wild rabbits aren’t calcium deficient, and have lovely skulls and teeth. The other theory is that wild rabbits have healthy teeth because their diet is based on grass, so their back teeth wear down correctly and retain normal mechanical function in the back teeth.
In fact, the two theories are not mutually exclusive: a calcium deficient rabbit will have poor bone quality, enabling the roots to push backwards into the jaw more easily once the jaw mechanics have gone wrong.
Whichever theory you subscribe to, the conclusion is the same - far too many pet rabbits are eating the wrong diet. Rabbits need a more natural diet based on hay and greens, with very limited quantities of rabbit mix or pellets. As well as providing adequate calcium, hay and greens based diets provide the abrasive green foods required for correct hind jaw function. For more information on healthy feeding, read our Feeding Symposium.
At the very least, unlimited hay is absolutely essential. Sunlight is not needed so long as the rabbit is eating a healthy diet, but owners of rabbits who do not have access to sunlight (houserabbits, show rabbits) must pay particular attention to their rabbit's diet to ensure bunny is receiving sufficient calcium and vitamin D.
Rabbits do not routinely require a calcium of vitamin supplement (too much calcium can be as harmful as too little) but fussy eaters or those with existing dental problems may benefit. If your rabbit falls into these categories, talk to your rabbit-experienced vet.
Can I check my rabbit’s teeth myself?
Checking the incisor (front) teeth is easy - clamp bunny between your knees on the floor, facing forward, lean over him and gently pull his lips back into a smile. You’ll see the incisors. Check them weekly.
Back teeth are virtually impossible to check at home, although some bunnies will allow their owners to slip a little finger in their mouth to feel for sharp ridges or spikes. Your job is to look out for any signs that might indicate a back tooth problem - for example lumps on the jaw, drooling, changes in food preference.
There’s a great section on how to spot tooth problems early in "Top to Tail", the Pet Plan/BHRA Handbook which is sent to all new members of the RWA.
How do vets check rabbit teeth?
A full dental examination requires a general anaesthetic or heavy sedation, and should include X rays of the skull. There is simply no other way the vet can be certain s/he has seen and examined every bit of the tongue, lips, cheeks and gums, let alone the teeth.
Examination using an otoscope enables the vet to perform a cursory oral examination, which is sufficient only for routine health checks (e.g. at the time of vaccination). If your rabbit is insured, annual dental checks like this are required for tooth problems to be covered by the policy.
However, if your or your vet has the slightest suspicion that your rabbit has developed a dental problem then inspection with an otoscope is insufficient and your bunny will need to be properly examined under sedation or general anaesthesia.
Rabbits with known or suspected dental problems are often poorly bunnies. They may not have eaten or drunk properly for some time, resulting in dehydration and malnourishment, or be developing problems such as "fatty liver".
All of these problems increase the risk of anaesthesia, hence such bunnies will usually be admitted for fluid therapy, force feeding, and pain killing medication, and only have their anaesthetic and dental examination when their condition is more stable.
Incisor (front teeth) problems
My rabbit’s front teeth are too long. What’s happened?
There’s at least three (possibly four) distinct patterns to front teeth malocclusion.
1. Hereditary - early
Some rabbits, frequently (but not always) round headed breeds like Lops and Netherland Dwarfs, develop overgrown front teeth at a very young age. This type of malocclusion is definitely inherited - affected rabbits should never, ever be bred from.
2. Hereditary - late
A second wave of front teeth malocclusion can develop at 6 – 18 months in some strains/breeds. These cases are probably hereditary but other factors will influence their development - see below.
3. Trauma
Rabbits who tug on their cage bars; or who are dropped/fall, may pull or knock their front teeth out of correct alignment.
4. Mechanical failure
If the back teeth have gone haywire as described above, the mechanics of the mouth fail completely and the front teeth may become maloccluded secondary to back teeth problems.
My rabbit hates having his front teeth clipped. The vet has suggested having his incisors removed. Is this really possible?
Yes! Rabbits manage fine without their front teeth. Maloccluded front teeth are useless anyway, even if clipped short, so your rabbit won’t notice much difference except that he won't need to be subjected to trips to the vet every few weeks for the rest of his life. In actual fact, rabbits can have all their teeth removed, although they then need a soft diet.
Please note that clipping overgrown front teeth is no longer recommended. Clipping places extreme forces on the tooth, compressing the sensitive pulp further up the tooth and sending a shock wave through the skull. It’s painful (which is why rabbits hate it) and it can also shatter the tooth roots, leading to infection. Having said that, not all vets are equipped with suitable dental burrs (although this is changing as a greater proportion of veterinary practices purchase equipment suitable for rabbit dentistry), and some rabbits hate being restrained for burring - so the quicker option of clipping may be the lesser of two evils in some cases.
Extracting the front teeth offers a permanent solution, but it’s may only be worth doing if the rest of the teeth are in reasonable shape. Hence, most vets insist on doing X-rays of the teeth and skull before taking out incisors.
Molar (back) teeth problems
My rabbit had small spurs on his back teeth at his last dental check, but they don’t seem to be causing any problems. Do they need to be removed?
Probably not at the moment, but it’s a very controversial area of rabbit dentistry.
Some Americans vets regard spurs as a normal part of bunny ageing, and "floating" (filing) back teeth as a routine procedure in older rabbits. But one influential British expert argues that spurs only appear when the mechanics of the back teeth are already disrupted, and that their presence indicate severe underlying dental disease.
Being pragmatic, if your bunny is otherwise completely well, with no sign of discomfort from his mouth, most people would watch and wait. The risk is that the spurs may dig into the tongue and cause sores and mouth pain. At the slightest suspicion of trouble, your bunny needs investigation (ideally including X-rays) to assess and treat the state of his back teeth and their roots.
Important notes
As mentioned at the top, this section of the website is being completely re-written. When completed, the new section will:
• Describe how rabbit teeth are supposed to work
• Outline what seems to happen when things go wrong, and the theories that try to explain why this happens
• Explain the early signs of dental problems to look out for in your rabbit
• Provide an overview of the kind of treatment options available for rabbits with dental disease.
There are several topics we haven't addressed in this temporary article which will be included in the revision. We've listed the topics we intend to include, but please let us know if you have ideas you think should be included.
This article was first written by Owen Davies
BVSc MRCVS and Dr Linda Dykes for the Winter 1998 issue of "Rabbiting On".
It was revised in March 2002 by Linda Dykes.
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