Equine Teeth

number corresponding to where they are in the quadrant. 

The quadrants are numbered one to four starting with the upper right side of the mouth, progressing to the upper left side, then to the lower left side, and eventually, the lower right side.

Some, though not all, horses have auxiliary teeth called wolf teeth and most horses also have four canine teeth, which are situated in the spaces between the incisors and the premolars. These teeth appear to have no function and may be vestigial teeth from prehistoric times.

Effective chewing

Effective chewing for horses is achieved through the grinding action of the cheek teeth of both the mandibular arcade (lower jaw) and the maxillary arcade (upper jaw). The grinding action of the occlusal (biting or contact) surfaces serves to tear fibre pieces apart, allowing them to be mixed with saliva before swallowing. Stabled horses fed a combination of forages and concentrates spend far less time chewing than horses that are grazing all the time. Their teeth do not get worn down as fast allowing for the development of abnormalities, which can cause discomfort for the horse. To maintain effective chewing for the stabled horse the cheek teeth must be smoothed out by floating or removing any sharp edges or hooks. In a normal set of equine teeth the chewing surfaces are somewhat angled and not completely flat. Veterinarians are careful when doing a dental float to maintain effective angles. Horses with neglected teeth cannot always have them corrected within one dental treatment. It sometimes takes several treatments to correct long standing dental issues.

Removal of teeth can also cause problems. All the molars in both the upper and lower arcades are situated in very close proximity with each other. Removal of teeth can result in the migration of some molars into the spaces left, potentially resulting in future problems with the grinding surfaces. Loss of a molar in the cheek teeth arcades can also permit food to be trapped between the teeth and gum. This is a condition called diastema and can result in periodontal disease in horses if not attended to very carefully.

Teeth of young horses

Horses are considered to be diphyodontous, meaning the young horse develops a set of deciduous or milk teeth starting within a week of birth. By two years of age, a young horse will have 12 incisors (three in each quadrant) and 12 premolars (three in each quadrant) and may be growing the first of their permanent molars. Between the ages of about two-and-a-half years and four-and-a-half years, they will get the balance of their molars, and their canine and wolf teeth if they are going to get them. They will also lose their deciduous teeth, both premolars and incisors, called caps at this point as they are replaced by permanent adult teeth. Sometimes it may be necessary for your veterinarian to remove caps on a young horse, as they don’t always get displaced by the adult teeth replacing them. 

Aging horses by their teeth

Because of the normal wear on equine teeth as well as normal tooth eruption in hypsodont teeth, it is possible to age horses with some degree of accuracy by examining their teeth. Examination of the incisor teeth will reveal wear patterns on the enamel, cementum, and dentin, which can help establish where the horse is in its life.

A horse that is under eight years old will have a marking on the occlusal surface of the incisor teeth in the lower jaw called the infundibulum or cup. As the horse ages, this wears away due to chewing and eventually the cup is no longer visible. As the occlusal surfaces of the incisors wear away over time,