Dental care in the horse involves the same principles as human dentistry; many of the diseases seen in people’s teeth are also diagnosed and treated in the horse. For example periodontal disease or disease of the structures surrounding the tooth is the number one cause of premature tooth loss in both horses and humans. Just like people, horses experience dental pain. Horses certainly can experience severe pain caused by sensation to the nerves supplying the upper and lower teeth. Horses also experience pain due to oral ulcers, impacted teeth, feed packing in to spaces (called diastema) between the teeth, fractured teeth, unopposed teeth erupting into soft tissues and tooth root infections causing abscesses. These are just a few of the ways in which horses experience pain and discomfort due to dental conditions.
Horses do have some important differences in the anatomy of there teeth. They are herbivores and their teeth are designed to grab and grind forage (grasses). Horses have two sets of teeth during their life and these teeth are constantly worn away by the actions of chewing and grinding. However, the horse possesses extra tooth or reserve crown below the gumline in the jaw and this erupts at a similar rate to the rate at which tooth is worn away. Horses have enough reserve crown to last the average horse well into there twenties and even horses in their thirties can still have a functional mouth with all teeth present and be able to chew.
This system of tooth being erupted and worn away must stay perfectly in balance or problems will quickly occur. Pain is the most common reason why the system gets out of balance. In response to pain, the horse will alter the way it eats and chews and this rapidly affects the wear patterns of the teeth. Because the horse chews in a complicated four part cycle, not simply side to side or up and down, theses points then act on the cheeks and tongue of the horse like a sawblade and cut them causing ulcers and if bacterial infection occurs abscesses.
Horses also have another important anatomical difference from people. Their upper jaw when viewed from the front is wider than there lower jaw and this means that the outer surface of the upper cheek teeth (closest to the cheeks) is unopposed as is the inner (closest to the tongue) surface of the lower cheek teeth. The edges of these teeth grow through the continual process of eruption but are not worn away and form razor sharp points similar to the teeth of a saw blade.
Equine teeth are made up of three tissues enamel, cementum and dentine. Enamel is the hardest but most brittle and this is what the sharp points are made of. Because of this brittleness, these points can be removed relatively easily providing relief for the horse and hopefully a return to a normal chewing cycle.
Another very important component of how the mouth is balanced is the diet. Horses evolved to graze with their heads down at ground level eating grasses for many hours a day. By altering their living and feeding conditions we alter the way their teeth wear. By forcing them to eat with there head up, providing short feeding times feeding grains, chaffs and pelleted feeds and when we do this we must be aware of the effects the changes have on the horse’s dentition.
It is important that a thorough visual exam is made of a horse’s mouth, as there are many other conditions that commonly occur in the horse’s mouth many of which cannot be diagnosed without visualisation. Ask your dentist to show you the inside of your horse's mouth so you can understand what's normal and what's not. All horse owners need to take responsibility for ensuring their horses receive proper dental care. Do your research and choose a qualified experienced professional who can explain what procedures they are performing and why.
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Article and images courtesy of Dr Shannon Lee BVSc MACVS (Eq Dent).