05/13/2020
Dental issues and equine performance
Your usually soft-in-the-mouth, responsive gelding has started throwing his head in the air when you pick up the reins or ask him to collect. While the behavior might be frustrating for you as a rider, it could be just as frustrating for him: His teeth might hurt. Anytime a horse shows a sudden change or resistance when working with a bit in his mouth, you should have your veterinarian check his teeth.
A horseās teeth are crucial not only for proper chewing and nutrition but also for proper performance. Dental problems can be quite painful and, in turn, can cause horses to exhibit certain performance-inhibiting behaviors. Often these problems are subtle or not even recognized as related to the teeth.
Sharp Enamel Points
Most dental problems that translate into performance issues are conditions that cause pain. The most prevalent one injures the soft tissues of the mouth.
Normal wear of teeth can lead to sharp points. These are probably the most common problem, since the lower jaw is about 30% narrower than the upper jaw. Because of this disparity, the outside edges of the upper teeth and the inside edges of the lower teeth donāt wear away as fast as the rest of the surface during chewing, leaving very sharp points of enamel.
Horses need a certain amount of exposed enamel to grind up food. In the wild, those sharpened projections donāt create much problem, but when we put tack on the horseās face and a bit in the mouth, this changes things.
Headgear such as bits, nosebands, and cavessons can place direct pressure on soft tissues that wouldnāt otherwise be subject to them.
Sharp points particularly affect horses that hold tension in their jaw muscles, either when ridden or stabledāsimilar to people who habitually clench their jaw. Thus, veterinarians perform routine dental care with two goals in mind: maintain dental health and provide comfort for the horse.
Routine dental care involves floating (rasping), smoothing off those sharp points. Sharp top teeth can lacerate the cheek tissue; sharp bottom teeth can lacerate the tongue. The horseās tongue is huge and long, nearly filling the oral cavity when the horseās mouth is closed. There is no place for that tongue to go to get away from ⦠sharp points on the teeth if the mouth is being held closed by tack.
Regular dental care to remove sharp points can help eliminate resistance behaviors such as mouth-gaping, jaw-moving, or sticking out the tongue when being ridden.
Horses are very tough animals and very stoic. They often keep doing their job and tend to keep eating, unless there is a very serious problem in the mouth. It has to be very serious, or a mechanical impossibility, for them to stop eating. Sometimes performance-related issues that are dental in origin can be quite subtle and almost impossible to confirm.
Malocclusions
A horse whose jaws and teeth donāt align
Some malocclusions, such as hooks that accompany wave mouth, can impede normal jaw motion during under saddle work. When the rider goes to collect the horse and asks him to flex at the poll, for instance, the hooks hinder movement in the temporomandibular joint (TMJ, which allows the horse to open and shut his mouth) between the skull and the first neck vertebrae, right in front of the poll.
Normally, when a horse flexes at the poll, the angle between the head and neck changes, causing the lower jaw to slide forward. If anything blocks that movement, such as hooks on the molars, and the horse canāt open his mouth enough to create space to free them, the jaws essentially lock together, the lower jaw canāt slide forward, and the horse canāt flex at the poll.
Trying to force him to flex may create pain in the TMJ joint. This problem can generally be alleviated with proper dental care and by not forcing the horse to keep his mouth shut.
A horse whose mouth is not forcibly closed when ridden can move his jaws to adjust their position and stay comfortable. In this case, the horse might not exhibit any performance problems, even though he may have hooks.
In other words, some horses simply continue to do their job no matter what. They have a high pain tolerance or an especially stoic personality and continue performing in spite of a dental problem other horses might not tolerate.