Digestive System > Pregastric Physiology

Dental Anatomy of Horses

Horses, donkeys, and zebras are obligate herbivores. They represent surviving twigs from a luxuriant bush of equid evolutionary history. Studying the teeth of ancestral equids played a critical role in defining the history of this important group of animals, and contributed substantively to our understanding of evolution in general.

The molars and premolars of the horse are known as cheek teeth. The cheek teeth slowly erupt to compensate for the constant grinding which wears away 2-3mm per year. For this reason, horses have very long teeth that are refered to as hypsodont which means "high tooth."

Estimating the age of horses by examination of their teeth is a commonly applied technique in the equestrian world.

Dental Formulae
Deciduous 3 0 3
3 0 3
= 12 Permanent 3 1 3(4) 3
3 1 3 3
= 20(21)

This skull is from a young horse shown by the long cheek teeth. In the maxillary arcade the cheek teeth extend into the maxillary sinus.

The cheek teeth do not always wear away evenly resulting in the formation of hooks and points. These hooks and points can cut into the tongue and buccal mucosa causing great discomfort to the animal. To avoid this, horses need to have their teeth ground down with a rasp periodically - a procedure called "floating".

Maxillary Arcade

The upper first premolars of horses are known as "wolf teeth".
Maxillary Arcade
Mandibular Arcade
Mandibular Arcade
(Lateral view)

Dental Anatomy: Index

Author: Melissa Rouge

Send comments to Richard.Bowen@colostate.edu