Chinchillas commonly have 20 teeth from birth - 4 incisor teeth and 16 molar-type teeth (also known as 'cheek teeth'). The upper incisor teeth usually have a right angle indentation, while the lower teeth are ground down to a point. Only about one third of the length of the incisor teeth is exposed from the jaw and all teeth are open rooted, which means they continuously grow approximately 2-3 inches a year throughout the chinchilla's lifetime. The incisors and molars are also separated by a gap known as the 'diastema', which enables a chinchilla to control what food is swallowed or expelled out from the mouth cavity.
Chinchillas have 5 teeth on the upper left, 5 teeth on the upper right, 5 teeth on the lower left and 5 teeth on the lower right and each tooth plays an important part in dental maintenance as the correct positioning of the opposing tooth is crucial and assures that each corresponding tooth is being constantly 'ground down'. The chinchilla's molar teeth act as a working unit in grinding down coarse food and the incisor teeth are used to bite into food sources or used as a defense mechanism against a predator.
The chinchilla's dental formula is: 2 x 1/1 (incisors), 0/0 (canines), 1/1 (premolar), 3/3 (molars).
A chinchilla has a hard layer of enamel over each tooth, which is made up of iron, calcium, phosphorus and other trace minerals. A normal healthy chinchilla should have dark orange teeth and anything less than this (dark yellow - white) will indicate a lack of calcium. The colour of the chinchilla's tooth enamel is vitally important as it shows a direct correlation to the amount of calcium a chinchilla has in its body and the potential risk of future tooth disorders. The pigmentation is influenced by the presence of iron in the enamel, which in turn is also influenced by the amount of calcium - for example, the more calcium the darker orange a chinchilla's teeth will be. It is important to regularly check chinchilla tooth pigmentation as the colour can change depending on daily dietary consumption.
In captivity chinchillas suffer from a multitude of tooth disorders, which in most instances are caused by the chin owners lack of knowledge, inappropriate nutrition and diet, lack of essential gnawing material, injury and trauma to the mouth cavity and poor chinchilla care/observation. Some common tooth disorders in chinchillas are:
Malocclusion is a serious medical condition where the misalignment of the upper and lower teeth do not come together properly when biting or chewing. It is not the misalignment in itself that proves the problem in Malocclusion, as this can be maintained with regular tooth filing but the fact Malocclusion is the main cause of 'Root Elongation' either to the incisor or molar teeth. This fatal condition happens when the roots of the teeth, which should grow either straight up or down, grow at angles (misaligned). Over time the upper roots tend to grow into the eye socket or nasolacrimal passage and the lower roots grow into the jawbone. Malocclusion is also a major contributory factor in 'Tooth Spurs' (also known as 'Burrs' or 'Points') which cause 'Tooth Elongation/Overgrowth' of the molar and incisor teeth. This condition is often misinterpreted as Malocclusion but is, in fact, a condition of its own that can be managed if caught in time. In most cases, Malocclusion is avoidable unless it has been acquired by a genetic influence.
As a preventative measure you should not breed together any chinchillas that you know to have any tooth abnormalities as there is a 50% chance of this serious condition being passed on to the unborn kits. A pregnant chinchilla should be provided with extra nutritional supplementation on the advice of a veterinary surgeon to aid in the development of a healthy fetus. Ensure a chinchilla is fed on a healthy diet of chinchilla pellets and good coarse quality hay. The side-to-side chewing motion needed to break down the hay will help a chinchilla file down their back molars evenly and provide plenty of hard items that the chinchilla can use to file the front teeth. Make sure all areas a chinchilla is allowed to explore, is safe to prevent any trauma coming to the mouth area and without fail make regular dental check-ups with a veterinary surgeon every 3 months. A yearly head X-ray is also recommended as sadly the symptoms of Malocclusion do not expose themselves until the latter stages whereas an x-ray will detect exactly where the tooth roots are so early treatment/maintenance can commence.
Tooth Elongation is the increased growth and length of a particular tooth, making it uneven to all the rest. Tooth Elongation is not the same as Tooth Spurs and is mainly caused from trauma to the mouth causing misalignment, lack or insufficient filing of the teeth, poor dentistry and tooth loss. If a chinchilla forcefully knocks the mouth area, this will cause pain and prevent him/her from eating correctly. A chinchilla may choose to not file the teeth due to pain that will then lead to an abnormal growth rate where all the teeth may not grow at the same length and at the same time. Tooth loss is also a major cause for elongation due to the loss of the opposing tooth. When a chinchilla grinds its teeth together during chewing, there will not be an opposing tooth to file against, this will cause the remaining tooth to grow longer and quicker than the rest of the teeth. There is no cure for Tooth Elongation only maintenance of the situation and the chinchilla will need to attend regular dental visits to a veterinary surgeon for the tooth to be clipped and filed. The chinchilla will need to be anaesthetised during the procedure and a short ‘day stay’ in the surgery will be necessary. A chinchilla with Tooth Elongation will also need to have a check-up every 6 weeks to maintain the length of the tooth and caution regarding tooth spurs should be maintained.
A seriously painful condition, where the roots of the lower teeth grow into the jawbone or the roots from the upper teeth grow into the nasal duct or eye socket. The main cause for tooth root elongation is from the misalignment of the teeth. This causes the teeth to grow at a slight angle and the roots to grow in an abnormal direction. Misalignment of the teeth can be due to genetics, malocclusion, tooth loss, trauma to the mouth area, jawbone fracture, lack of proper nutrition during fetal development and poor dental management such as, a lack of items for a chinchilla to gnaw on or not having regular dental check-ups. This situation is a serious 'untreatable' medical condition that can lead to nasolacrimal blockage and eventually proves fatal to a chinchilla. The only prevention for this painful condition is to provide a good nutritional diet during fetal development and for the rest of the chinchilla’s living life. You must prevent the misalignment of teeth by offering a chinchilla plenty of hard items to file the front incisors and good quality coarse hay to help keep the back teeth in line and filed to a good length. No trauma must come to the mouth cavity therefore the environment a chinchilla is allowed to explore should be safe and various levels easy to access to help prevent falling.
A sharp pointed projection from the tooth that will need urgent medical attention. Tooth spurs are a condition relating to the misalignment of the chinchilla’s teeth where the teeth do not grow normally straight up and down but lean slightly in any direction causing the teeth to not be filed evenly. This uneven wear eventually causes spurs to form and grow, inflicting cuts to the mouth and tongue. The cuts can become infected and there will be immense pain when eating. The spur will need to be removed and the surface filed by a qualified veterinary surgeon as there is no complete cure for this disorder only maintenance. Tooth spurs will continue to become a problem for a chinchilla, as generally when you have one spur, there will be more to follow during the chinchilla’s remaining lifetime. A chinchilla will need to be anaesthetised during this type of operation but with extra vigilance and if caught in time a chinchilla can continue to live a long and happy life.
The total absence of a tooth causes a problem for the opposing tooth as it cannot be filed appropriately. White teeth are also a sign of weakened teeth, which can be a contributory factor towards tooth loss. If a chinchilla has had severe trauma to the mouth due to being knocked or falling, the tooth that absorbed most of the impact can die due to nerve ending damage. The tooth can also die from improper diets that are high in sugars and fats causing decay. The only prevention for a tooth not to fall out is from excellent nutrition during the fetal development and throughout the rest of the chinchilla’s life. No trauma must come to the mouth area therefore any obstacles for a chinchilla to jump on to should be sturdy and the environment he/she is allowed to explore should be safe (chinchilla-proof).
Common Symptoms Of A Tooth Disorder:
All chinchillas that carry a tooth disorder will expose the following symptoms (amongst others):
- Wet and watery eyes
- Pawing at mouth
- Disinterest in gnawing objects
- Crumbs left after eating pellets
- Less hay consumption
- Gag or squeal during eating
- Decreased food intake and weight loss
- Difficulty drinking from water bottle and frequent tooth grinding
- Lumps under eye socket and jaw bone (malocclusion)
NOTE: It is important to take a chinchilla for regular dental check ups and a yearly head X-ray to prevent tooth disorders going unnoticed or becoming incurable!
Further Reading Relating To Chinchilla Teeth:
Chinchilla A-Z Health & Sickness Bible, Chinchilla Examination, Chinchilla Health, Illness, Sickness & Disease, Minerals And The Relation To Chinchilla Disease, Nutrition, Supplementation, Vitamins And The Relation To Chinchilla Disease.