Rabbit dental disease – acquired or congenital?

Rabbits continue to be seen in increasing numbers in general practice and perhaps the most common problem we see them with is dental disease. The causes of dental disease are variable but can be broadly classified as being either congenital or acquired.

Posted: 12 November 2019

Rabbit dental disease – acquired or congenital?

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A. Congenital dental disease is mostly seen as malocclusion. It’s easy to diagnose, especially if it affects the incisor teeth, and tends to be more common in small and dwarf breeds. The lower teeth protrude forwards from the mouth, and the upper teeth overgrow and curl round inside the mouth. As these upper teeth grow, they can cut the soft tissues causing pain, bleeding and infection. They make it difficult and painful to feed normally.

B. Acquired dental disease is usually related to poor nutrition, trauma or ageing. Treatment is aimed at returning normal anatomy and function and controlling any associated infection and inflammation.

Clinical signs

Sometimes the client won’t even be aware there is a problem, but since this is one of the commonest reasons a domesticated rabbit becomes unwell, always be on the lookout for any of these problems.

  1. Anorexia – ask the owner how often they’re adding fresh hay and nuggets. Many owners are keen to feed their pet, but how many really notice what is being eaten?
  2. Weight loss – make sure you check their weight every time they’re examined. Get owners used to handling and feeling their pet. The Body Condition Score is a useful guide.
  3. Drooling – look for signs of wet fur and saliva dribbling from the mouth.
  4. Hair around the base of the incisors – hair often gets entangled and will be visible around the base of the teeth.
  5. Ridges in the enamel – check the front surface of the incisors. Use a light to highlight the ridges and feel with your fingers.
  6. Pain – this is associated with dental infections. Many rabbits will suffer significant discomfort if left untreated and will spend time grinding their teeth.      
  7. Poor coat – rabbits with overlong incisors wont groom themselves as often and may develop a ‘moth eaten’ appearance.
  8. Tear overflow – many rabbits with inflammed or diseased maxillary apices will have compression of the tear ducts, causing tear overflow or dacrocystitis.
  9. Dirty bottom – uneaten caecotrophs will stick to and accumulate around the perianal region. These rabbits are at risk from myiasis.
  10. Swellings – bony swellings along the line of the mandible or around the maxilla may indicate abscesses associated with infected cheek teeth.

What treatments are available?

The aim of all rabbit dental treatment is to;

  • Correct dental length
  • Restore normal occlusion
  • Remove diseased teeth
  • Treat any associated complications e.g. Abscesses
  • Correct any management triggers e.g. Poor diet

1. Incisor malocclusion

For many years’ vets have been attempting to help these animals by ‘clipping the teeth’. This is not recommended as the procedure is painful and the teeth can become fractured longitudinally. A more appropriate way to temporarily tackle the problem is to trim the teeth with an electric bur.

A. Electric bur

If an electric dental bur is used, it’s usually recommended that the animal is sedated or given an anaesthetic to avoid stress. The teeth should be cut horizontally at the desired length. Use the drill at full speed and with a light pressure. Avoid thermal tissue damage by keeping it moving on the tooth at all times. Extra care should be taken with the lower incisors as the pulp cavity is often above the gum line. Look carefully for the characteristic pink pulp tissue line and cut 1-2mm above this.

B. Incisor extraction

  1. Cut the gingival attachments - release the tooth from the gingival pocket by gutting the gingival attachments. This can be achieved using a scalpel blade (a narrow No 11 blade), or sometimes more effectively using a 21G or 23G hypodermic needle.
  2. Periodontal ligament – this needs to be broken down. An incisor elevator is then inserted along the line of the tooth by applying gentle and constant pressure. Repeat this action on both the lateral and medial edges towards the distal end of the tooth, taking your time. If you rush at this stage, there is a risk of tooth fracture. If a tooth does fracture, the rabbit must be checked a few weeks later. By this stage the crowns will have re-erupted, allowing for a second attempt at extraction.
  3. Loosen and remove - with patience and persistence, the tooth will become loose. It is a good idea to work from tooth to tooth, loosening several teeth all at once. Make sure you remove all 6 incisors, even the small upper peg teeth. In spite of their small size, take even more care with the peg teeth as they fracture so easily. By using a gentle rotating action, the tooth can be carefully extracted, taking care to extract it along the curvature of the tooth. If excessive traction is used, there is a risk that the tooth can be fractured. Do not twist the tooth in its socket as this risks causing a fracture as well.
  4. Destroy the germinal tissue - it’s essential that the germinal cells are damaged sufficiently to prevent the tooth from regrowing, often at an even more abnormal angle and shape. This can be achieved by pressing firmly back into the socket. It’s always worth warning the owners that there is a small risk of regrowth after extraction even when this method is used.
  5. Heal by granulation - after extraction, the gingiva will look swollen and red. There is usually a moderate amount of bleeding which can be controlled with swabs or packing. The gingiva can usually be left to heal by granulation, which will happen over a few days. The tissue can also be closed with 5/0 absorbable suture material, though there is a risk of enclosing a pocket of infection.
  6. Analgesia - peri-operative analgesia will help, as will postoperative analgesia for several days. Opiates and NSAID’s are all routinely used.
  7. Fluids and nutritional support - in most cases, the rabbit should be bright, alert and eating within just a few hours. If there is any delay in returning to normal feeding, supportive fluids and calories must be given.
  8. Excel Dualcare - when additional food and fluids are required, it’s important to use the best quality, long fibre foods available. At Burgess Pet Care we have a great product called Excel Dualcare, which can be mixed with water and syringe fed.
  9. Grooming - a healthy rabbit will use its incisors for grooming, so if these have been removed, the owner should be advised to help prevent the hair from matting and clumping by starting a daily grooming routine.

2. Acquired dental disease

i. Reduce the crown height

Overgrown incisors and cheek teeth should be trimmed using a high-speed dental bur under sedation or anaesthesia. Nail trimmers, rongeurs and other manual cutting tools should never be used as tooth root damage and fractures are likely to occur. If treated promptly, this process can be curative especially if any dietary insufficiencies are corrected.

ii. Extract the problem teeth

This must always be done under an anaesthetic, and is indicated for any tooth that is loose, infected/abscessed, fractured or severely mal-occluded. Depending on the access to the tooth, the problem can be extracted intraorally or extra-orally. Post-surgery pain relief and nutritional support must be offered.

A variety of dental equipment will be required, including;

  • Mouth-gags
  • Cheek dilators
  • High-speed dental handpiece
  • Cheek guard
  • Dental burs
  • Crossley incisor and molar luxators

Take a look at some rabbit dental equipment >

3. Abscesses

Abscesses on a rabbit’s head or jaw are often associated with the periapical area of an infected incisor or cheek tooth. Mandibular abscesses are more common than maxillary abscesses. Treatment includes;

  • Removal - if you are able to fully excise the whole abscess without rupture, this is a great option.
  • Curette – if the abscess is clearly attached to bone, then careful excision down to the bone, followed by positive curetting of the bone to remove all diseased and infected tissue may work. It’s worth flushing the site copiously afterwards to minimise any infective organisms being left behind.
  • Granulate – in many cases the wound may be left to heal by granulation. This will allow for daily cleaning. The wound should slowly close.
  • Marsupialisation – lancing, emptying and curetting the abscess wall, followed by suturing the abscess wall to the skin (marsupialisation) is an option worth considering.
  • Conservative - occasionally it may be acceptable to leave the abscess untreated, particularly if there is no evidence of pain or loss of appetite.
  • Euthanasia - ‘treat the animal, not the disease’, so be prepared to offer this option if the animal is unlikely to make a good recovery.

Prevention - 5 ways to avoid rabbit dental disease

  1. Regular veterinary examinations - pet rabbits should visit a vet at least once a year. Encourage this by using your emails, Social Media and waiting room posters. Talk about the need for the health checks from day 1.
  2. Breed selection – we see more malocclusion issues with smaller and dwarf breeds such as the Netherland dwarf. In these breeds skull length is reduced, but the mandible is not always proportionally reduced in size. This condition is termed maxillary brachygnathism.
  3. Early diagnosis – take every opportunity in your practice to check the dental anatomy of your patients. Spend a couple of minutes palpating the face and jaw and look into the mouth using a light source and gag. Ask lots of questions about diet and behaviour, as many of the clues of a problem will be found.
  4. Early treatment – don’t wait too long for the problem to become too advanced. Prompt and staged treatments will often be more successful.
  5. High-fibre diet – this is absolutely essential to avoiding dental disease in rabbits. Owners should feed their pets plenty of hay and grass. At Burgess Pet Care we produce a range of high quality fibre rich diets. Find out more by clicking the links. Our hay range includes;

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