The angle of incidence is the angle formed where the upper and lower incisor teeth meet. This angle is approximately 160º to 180º in young horses and becomes less than 90º in older horses. As the horse ages, incisors appear to slant forward and outward.
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Originated from the American Youth Horse Council's
Horse Industry Handbook
The umbrella organization providing leadership and resources for the youth horse industry.
1-800-TRY-AYHC