Ensuring all equine in South Carolina live in a safe, healthy and nurturing environment.
Lexington South Carolina 803-729-3692
The tooth, the whole tooth
by Ken Marcella, D.V.M.
The only time many owners look in their horses' mouth is to check age or to give a dewormer, but it is important to pay as much attention to our horses' dental health as we do to other areas of equine care. Tooth problems in horses are common because their teeth never stop growing.
An oral exam is the best way to check for dental problems, but other signs of problems are poor coat and condition; dropping a lot of feed when chewing; turning the head to one side or chewing abnormally; and the presence of whole corn or other undigested grains in the manure.
Poor athletic performance, behavioral problems and colic can also be caused by bad teeth.
Add in the economic loss of feeding grain the horse can't properly chew and digest, and equine dental health becomes an area that deserves a closer look.
Horses' teeth are totally different than ours. Equine teeth have very deep roots located far away from the actual chewing surface. Horse teeth are large, and the majority of the tooth is located deep within the bone of the upper or lower jaw.
Horse teeth are wider at the chewing surface than at the root. As a horse ages, its teeth continue to grow and push further out from the root or base of the jaw. Ideally, the upper and lower teeth fit tightly on top of each other and wear each other down while the horse chews. Humans have a flat occlusal surface (the surface where the upper and lower teeth touch), while horses have an angled occlusal surface.
This design helps in grinding grain, but equine teeth are spaced so they can easily trap food. Trapped food can lead to gingivitis, or inflammation of the gum lining, and ultimately to tooth and gum disease.
The shape, size and method of growth of equine teeth cause specific problems. If a horse is born with an upper jaw that is slightly longer or shorter than the opposing lower jaw, the teeth will not line up correctly. Because the upper tooth depends on a matching lower tooth to help wear its surface normally, and vice versa, jaw misalignment spells dental problems. Horses with well-matched jaws will wear teeth more slowly and evenly, often increasing their life span.
An unopposed tooth will continue to grow, resulting in a hook or a point. Hooks occur on the front of the upper teeth and the back of the lower row of teeth. These points can become sharp and cause chewing difficulty, irritating the gum and possibly leading to an abscess. Points and edges can interfere with the bit and make horses pull away, toss their heads, or display behavior that is often incorrectly attributed to training problems.
Uneven growth or wear can lead to "wave-" mouth horses, where the surface of the teeth, when viewed from the side, looks like a wave, with some teeth being high and some being low.
Due to trauma, such as a kick or a fall, horses can even lose a tooth occasionally. This gives the opposing tooth nothing to wear against, and it will continue to grow out from the jaw. In severe cases, this unopposed tooth will even keep growing into the empty space left by the lost tooth. This can bind the jaw movement, making it very difficult for the horse to chew.
Severe dental problems are frequently seen in older horses and are a prime cause of poor weight, poor coat and general lack of condition. But young horses can have dental problems as well.
Foals begin to get teeth at a few months of age. These first teeth are sequentially replaced by permanent teeth over the next five or six years. After that point, mature teeth continue to grow, wear and gradually wear out over the course of the horse's life.
Routine dental exams and tooth care should not be overlooked. Your horse needs a routine check for points, hooks or sharp edges. Veterinarians use a metal speculum or mouth gag to aid in the examination of the teeth and gums. If points are found, your vet will file the sharp edge smooth using a number of tools called floats. As a horse matures, his teeth should be floated annually.
How common are dental problems?
Dental disease was found in more than 80 percent of the horses in a recent study at the University of Illinois. Five hundred horses, from six months to 30 years old, were examined to try to determine the extent and severity of dental disease.
Sharp points, resulting in ulceration and inflammation of the gums, were seen most commonly in horses under 10 years. Abnormal wear and "wave" mouth conditions were seen in older horses, as was periodontal disease.
Other equine dentistry to help keep horses chewing normally includes reconstructive alignment surgery, tooth extractions, and dental mold replacements.
Your veterinarian can instruct you on the proper method of examining your horses' teeth. Be careful and follow directions, because a horse's jaws are powerful, and teeth can be sharp.
Ken Marcella, D.V.M., is based at the Chattahoochee Equine Center in Canton, Ga.