The Importance of Maintaining the Health of Your Horse's Mouth:
Dropping feed, losing weight, poor coat condition, loose stool, resenting bridling, fighting the bit, running away with the bit, rearing-- these are some of the common ways that your horse will tell you about a dental problem. But the most common way is silence. Many horses have mouth problems that we know must be uncomfortable, yet they continue to do what we ask without complaint. This is why a thorough dental exam is an important part of every health examination and crucial for the horse being seen for a problem, whether colic, lameness or behavioral issues.
More than just “floating teeth” the dental exam consists of looking at the musculature of horse’s head, palpating his cheeks and temporomandibular joints, and examining his mouth from front to back. Many people do not realize that a horse’s incisors, those teeth in the front of his mouth through which you pass the bit, are just the tip of the iceberg. Horses have teeth in their mouth back to just under their eye.
Adult horses have 36- 42 teeth in their mouth. The incisors are the 12 teeth in the front of the mouth, through which you pass the bit. Six upper and six lower, these teeth are used by grazing horses to clip the forage that they are eating. Once clipped, the grass is pulled into their mouth by the lips and tongue and delivered to the “cheek teeth”, 6 upper and 6 lower premolars and molars on each side of the mouth, which grind and crush the structural fibers of the forage into small enough particles for easy digestion.
The remaining 6 teeth are the canines- the stubby but sometimes sharp fangs in the bit space-- and the “wolf teeth” the upper first premolars, up against the cheek teeth. These teeth really serve the horse no purpose and are vestigial remnants of evolution.
Horses have deciduous (baby) teeth as well as their permanent (adult) teeth. All 12 of their incisors come in first as baby teeth and the first 3 upper and lower cheek teeth come in first as baby teeth also.
The structure of the horse’s tooth is quite different from ours and that of other omnivorous and carnivorous mammals. Our teeth have a cap of hard enamel covering the softer structural dentin underneath. Instead of this enamel cap, horses have a series of folded up enamel ridges on the chewing surface of the tooth, kind of like a piece of ribbon candy. These enamel ridges provide a hard rough surface for grinding forage and grain.
This enamel wears down constantly as the teeth, upper and lower, grind against each other. Horses have a “reserve crown” of tooth that grows in at a rate of about 1/8th inch per year. This is one of the primary reasons why horses need their teeth floated. As the teeth wear, sharp edges of enamel can remain. These sharp edges can rub against and hurt the insides of their cheeks and tongue, especially when we put a bit in their mouth and a bridle over their cheeks.
The reserve crown does not last indefinitely and in their late teens to twenties, the enamel begins to wear away completely, exposing the soft dentin underneath. The dentin is not nearly so hard as the enamel, so horses may have a difficult time grinding up their food. The upper and lower teeth may not wear out at the same rate, allowing a hard enamel tooth to wear into a softer dentin tooth. This can cause sores and the overgrown tooth can interfere with the normal chewing motion of the jaw.
So, what can the dental exam reveal? Following is a list of the common terms for dental abnormalities. Descriptions of these abnormalities is beyond the scope of this article, but will be explained by your veterinarian if found in your horse’s mouth.
Dental examination may also reveal pain or arthritis in the temporomandibular joints or asymmetry of the muscles used to chew, which are indicative of problems inside the mouth. Your veterinarian can also provide you with an estimate of your horse’s age. Keep in mind that this is an estimate and the older the horse, the greater the error there will be in this estimate due to normal variation in the wear of the horse’s teeth.
Why is it important to have this examination done? It is beneficial to maintain your horse’ s dental health for reasons of nutrition and performance. If your horse can chew his food better, he digests better and makes better use of the nutrients in his feed. Not only is this beneficial for him, but it provides for less waste of feed (therefore waste of money spent on feed). Less obvious but just as important is how dental health affects performance. When you put a bit in your horse’s mouth, a bridle over his cheeks, pull on his head and ask him to yield to you, he will be much more likely to cooperate smoothly if he doesn’t have interference with motion or pain in his mouth. Training issues, behavioral issues and even some “lamenesses” should be addressed, in part, with a thorough dental exam. This exam should also be part of your semi-annual health exams by your veterinarian.
What can be done to fix the problems found during the dental exam? “Floating teeth” is the commonly used term for performing equine dentistry. Floating consists of filing the teeth using an assortment of specially designed metal files to shorten and smooth the surfaces of the teeth. Using a variety of hand and power tools, your veterinarian can remove the enamel points or other sources of discomfort or interference in the horse’s mouth. Canine teeth can interfere with the bit and may be cut down to the gumline to reduce this interference. Wolf teeth can be painful if struck by the bit and are often removed before the horse goes into training.
Not all problems can be completely corrected, but they can be managed to your horse’s benefit. Maintaining your horse’s dental health will require regular check-ups and floating due to the fact that their teeth continue to grow even after being floated. Many times only partial correction can be made during one visit, and time must be allowed for the teeth to grow a bit before further corrective work can be done.
It is important to know that the practice of equine dentistry (floating teeth) is limited to licensed veterinarians in the State of New Mexico and many other states. While many laymen claim to be "equine dentists" their training varies widely. They are not licensed to use drugs for sedation, control of pain or infection, nor have they been trained in the proper use and ill effects of such medications or the dental procedures they may perform. You have no recourse against them if they damage your horse's mouth. Ask questions of these people if they would like to work on your horse, and don't hesitate to contact your veterinarian.
Dr. Cameron has had a special interest in Equine Dentistry since veterinary school. Dr. Cameron spent his first few years in practice working closely with Certified Equine Dentist, Jim Ford. Dr. Cameron continues to develop his practice of equine dentistry further since taking over the equine practice from Eldorado.