Equine Wellness: Dentistry

Horses require regular dental care, not only to remove sharp points, but to look for and assess any potential abnormalities that could be causing them discomfort or more serious problems.

Horses have a very unique dental structure. They have two major divisions of teeth; incisors which are in the very front of the mouth, and cheek teeth, which are made up of premolars and molars. Incisors are used for grasping and tearing feed, while cheek teeth are used to grind feed. The premolars and molars are lined up tightly lined up beside each other. This is called a dental arcade. There is a large space between the incisors and the cheek teeth. Canine teeth can be found in this large space.

Horses evolved with a special kind of tooth, called hypsodont teeth. These teeth are tall, and continue to erupt from the gum long after forming. These teeth develop in the jaw of the horse. Cementum (hard material that forms part of the tooth) and bone are deposited, which eventually pushes the tooth out of the skull and through the gum line.  The exposed part of the tooth is called the crown, while the portion left in the jaw is called the body or reserve crown. On the surface of the tooth, there is enamel and dentin. The enamel is very hard, and is very important for grinding feedstuff. It is very important that the chewing surfaces of the teeth have enamel-to-enamel contact. If the teeth are offset, then the enamel can come into contact with the much softer dentin. This then results in the dentin wearing away rapidly and deforming the softer tooth.

Your horse chews feed by chewing in a circular motion, where the lower jaw slides along the upper teeth. This circular motion is responsible for maintaining the occlusive surface of the teeth. As horses eat smaller feed particles, this motion is reduced. While eating grain/pelleted feed, horses chew in almost an up-and-down manner.

Due to their continuous eruption and wearing of teeth, horses have an increased risk of dental disease. Horses rarely have problems with tooth decay or gum disease. If a tooth is lost or worn abnormally, the opposing tooth will continue to erupt from the gum line. This dominant tooth continues to wear into the opposing arcade without having appropriate grinding surface. This magnifies the abnormality. Eventually, this can result in mouth pain and abnormal chewing patterns. Abnormal chewing can result in weight loss, tooth infection/abscess, sinus infection, or even impaction colic.  

For a long time, it was believed that horses only develop sharp points, and all that was needed was a regular floating to remove sharp points. However, now it understood that this is not the complete picture of dental care. The most important part of dental care is a thorough dental exam. Ideally, depending on your horse’s age and performance level, your veterinarian should complete a thorough dental exam every six months to one year. It is important to complete a complete oral exam, and not just look at the teeth as other disease processes may be present in the horse’s mouth. During the assessment, your veterinarian will look for any signs of tooth decay (cavities), fractured teeth, periodontal (gum) disease, oral soft tissue injuries or tooth root abscess.

For a dental exam, your horse is sedated, and then your veterinarian will place an oral speculum. This allows us to visualize the horse’s entire mouth. All of the tooth surfaces are examined, along with the gums, tongue, hard/soft palate, and external facial structures.

Many dental abnormalities occur due to abnormal occlusion, which forms when there is an abnormal chewing pattern or missing teeth. Eventually a dominant tooth is created, which unevenly wears the opposing tooth. Here are some common abnormalities found on dental examination.

  • Sharp points: caused by uneven grinding surface. Points tend to occur on the buccal (lip) side of the upper cheek teeth, and lingual (tongue) side of the lower cheek teeth. If left untreated, these points can form ulcerations in the mouth, and cause head throwing or pain with the bit.
  • Hooks: formed when teeth are unopposed. This is most common when the opposing tooth is lost, or at the front or rear of the dental arcade. If left untreated, they will eventually impact the opposite gum.
  • Wave mouth: caused by several teeth becoming dominant. The dental arcade will have high and low sections. For this condition, it is important to identify the dominant teeth and make it level with the arcade. The opposing arcade that has been worn away will be left to grow back. This condition requires life-long monitoring.
  • Steps: occurs when a tooth is longer than the rest of those in the entire arcade. Usually occurs when opposing cheek teeth is missing and/or diseased. Requires life-long monitoring.
  • Shear mouth: occurs when horse is only using one side of its mouth, resulting in one side being worn faster than the other. Usually see a slant to the incisors as well.
  • Deciduous teeth problems: when horses are approximately 2.5 years to approximately 4.5 years old, they shed their deciduous or milk teeth. These are commonly called caps.  If these caps are not shed properly, it can cause young horses to have pain while chewing.

In addition, incisors continue to erupt as a horse ages. Incisors can also wear abnormally or become loose. Uneven incisors will influence normal side-to-side chewing motion, and can even prevent normal occlusion of the cheek teeth. Incisors are evaluated and treated after the cheek teeth are treated.

It is essential to do a thorough dental examination every six months for young (<5 years) and older (>20 years) horses. In our practice, we recommend a six month dental examination for all horses showing, as sharp points and even minor hooks can greatly impact your horse’s comfort while performing. Your horse’s health and survival depends on their ability to chew and grind feed. Proper dental care allows your horse to eat better, be healthier and have fewer mouth problems.

More information available on Dr. Kurtz’s Equine Wellness: Dentistry video.

2018-03-22T00:11:39+00:00