Equine malocclusion

An equine malocclusion is a misalignment between the upper and lower jaws of a horse or other equine. It results in a faulty bite with the upper and lower teeth failing to meet correctly. Malocclusions can cause pain to the horse and may also lead to weight loss and other eating problems related to poor chewing or loss of appetite. In addition, discomfort can lead to poor behavior when the animal is ridden or driven, particularly if a bit is used in the horse's mouth.

Caudal hooks are defined as when the dominant lower or upper last molar overhang the opposing molar. They can be hereditary and may result because a horse is born either parrot-mouthed or monkey-mouthed. They can also be caused secondary to another molar malocclusion that forces the jaw to disalign. This malocclusion results in problems for the horse when eating. It prevents the horse from chewing side to side freely which causes incorrect and excessive tooth wear. The soft tissues of the mouth can be damaged because the hooks are sharp and can cut them. Caudal hooks will also cause discomfort to the horse during riding. To fix caudal hooks, the dominant molar must be reduced, preventing extreme wear to the opposing molar, and rounded so that the soft tissue is not traumatized.

Rostral hooks occur when the dominant upper front premolars overhang the lower premolars. They can be hereditary or developmental meaning that the horse can have an overbite at birth or can have another malocclusion that forces the disalignment of the jaw. Rostral hooks can result in improper and extreme molar wear especially to the opposing lower premolar. Other problems include bit problems and soft tissue damage. Fixing Rostral hooks requires that you reduce the dominant portion of the upper premolar and round the unopposed portion smoothly towards the gum. Preventive maintenance is required to prevent recurring Rostral hooks.

When there is excessive height to the lower premolars, the horse has a condition known as ramps. They occur when the upper from the premolar deciduous cap or baby tooth is kept resulting in the abnormal growth of the permanent premolar. The problem with ramps is that they prevent the horse from freely chewing side-to-side. This causes improper and over wear of the molars. It will also, along with an underbite, cause severe discomfort when a bit is placed in the horses mouth. To solve the problem, the dominant tooth must be reduced to allow the opposing one to recover.

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