It is very easy to let your horse’s dental care fall to the back of your mind as he or she gets older. However, this is when a healthy mouth becomes most crucial in order to prevent excessive weight loss.
Horses are a hypsodont species. This means their teeth have a long crown and continue to erupt (not grow) throughout their lifetime. As the teeth erupt, they are simultaneously worn down by the grinding action used for chewing grass, hay or haylage. Domestication of horses today has resulted in the feeding of large quantities of concentrates, which require less grinding than high fibre hay or haylage. This alters the natural wear pattern of the cheek teeth and increases the need for equine dentistry to correct common abnormalities such as sharp enamel points of the cheek teeth.
The width of the cheek teeth narrows as they reach the end of their eruption in elderly horses and can lead to problems such as ‘diastema’. This is a space that develops between the individual teeth in which food material can become impacted. As food builds in this space, it becomes very painful and can cause the horse to ‘quid’ or drop food from their mouth. If not treated, diastema can lead to gum disease (periodontal pockets) or infection of the tooth root, which may then affect the surrounding bone or cause infection within the horse’s sinuses. If detected before complications arise, food material packed between the teeth can be flushed free and if necessary the gap widened to a point that food is no longer trapped. In more severe cases, a long course of antibiotics or even flushing of the sinus may be required. Horses with diastema will benefit from regular 6-monthly dental checks to prevent further problems occurring.
Another common abnormality detected in aged horses is overgrowth of individual teeth. Older horses are prone to losing teeth as the roots become shorter and the pressure from adjacent teeth keeping them in place becomes less. After tooth loss, the opposite tooth then loses its normal wear and has the opportunity to overgrow. Overgrown cheek teeth can also be a secondary complication of diastema. In this case, a space develops into which the opposing tooth can grow into without being worn down. When overgrowth of a cheek tooth occurs, the regular chewing motion of the jaw can be affected as the overgrowth can ‘lock’ the jaw. When this occurs the horse cannot chew effectively and so proper mastication is not possible, leading to severe weight loss in some cases. Overgrowths can be treated with manual or motorised rasping to reduce their height. It is very important not to reduce the height entirely in one treatment as the heat generated during excessive use of motor equipment can damage the sensitive pulps of the tooth. They can then become exposed and infected, ultimately leading to death of the tooth. Usually they are corrected by a few millimetres a time over 2 or 3 treatments 2-3 months apart. It is not usually necessary to completely reduce the height of these teeth but only to correct them so there is no more interference with chewing.
In order to maintain a healthy mouth in older horses, it is advisable to have their teeth checked by a vet or fully qualified equine dental technician every 6 months or at the very least once a year.