Excerpted from: Oral Health in Equidae

With permission from, and special thanks to: Dale Jeffrey and The Academy of Equine Dentistry

Anterior/posterior movement of the mandible (APM): Forward and backwards movement of the mandible in relation to the maxilla. This movement is extremely important to the horse.

Arcades: The individual rows of teeth, also referred to as batteries.

Axial flow (AF): The flow of food through the tables of the premolars and molars.

Bishoping: a deceitful practice of chiseling the incisor cups and blackening them with silver nitrate or other chemicals creating younger appearing teeth.

Bitseat: The rounded and smooth rostral surfaces of the first cheek teeth, placed to enhance athletic performance, and eating efficiency.

Buccal (buck-al): of or pertaining to the cheek, the cheek side of the molars.

Calculus: Calcified deposits on the surfaces of teeth sometimes referred to as tartar

Canines: Conical simple crowned teeth found between the cheek teeth and the incisor teeth. They are variously called “fighting teeth, fangs, tushes, tusks or bridle teeth”.

Cap: Deciduous or primary tooth remnant, sometimes called milk or baby tooth remnant.

Cusp: A pointed (mostly enamel) eminence on or near the surface of a tooth.

Decay: Decomposition of organic matter by the action of organisms.

Diastema: A space between teeth.

Deciduous: Baby teeth or milk teeth that precede permanent eruption.

Equilibration: The general maintenance of horses teeth through balancing by cutting, filing and burring, thus reducing protuberant, blocking and restricting teeth to give full lateral excursion of the mandible, a more perfect occlusion of the cheek teeth and incisors, while maintaining incisor and molar table angles and restoring anterior and posterior movement of the mandible thus relieving pain, increasing tooth life, enhancing performance and improving overall balance and condition.

Excessive Transverse Ridging (ETR): The excessive abrasion of the cementum in the softer areas of the tooth, and lack of abrasion to the enamel in the harder areas of the tooth, which creates the onset of ETR. The cementum is worn from food abrasion laterally near the anterior and posterior margins and in the mesial (middle) area of each tooth.

Galvayne’s groove: A vertically-oriented, tapering groove in the lateral surface of the permanent upper lateral incisors of the horse which begins to show above the gum line at ten years old, is half way down the incisor at fifteen, clear down at twenty, half gone at twenty five, and clear gone at thirty years of age. Named after it’s discoverer, accredited horseman, Sydney Galvayne.

Gingivitis: Inflammation of the gums.

Hook: As used in equine dentistry; a pointed end or peak developed on a tooth through abnormal wear. Generally not in occlusion with opposing pathology. A malocclusion.  (Also see, Ramp.)

Incisors: Teeth found at the front of the horse’s mouth; the “nippers”. In horses there are twelve deciduous and twelve permanent incisors.

Lateral excursion: Outward movement of the mandible, to each side. Normally measured in percentage. Any teeth blocking lateral excursion in the horse are problem teeth.

Lingual: Of or pertaining to the tongue; to the tongue side.

Malocclusion: In horses teeth; the inability of the arcades of molars or incisors to occlude, fit together properly or work effectively/efficiently.  (Also see, Occlusion.)

Mandible: The lower jawbones; the inferior jaw of the horse.

Maxilla: The upper jawbone or stationary jaw containing the wider arcades of molars in the horse, which acts as a millstone against which the lower “grinders” (cheek teeth) work.

Molar: One of the accessional or permanent teeth. Molars have no deciduous predecessors in the dental arcades.  (Also see, Premolar.)

Monkey/Sow Mouth: (See Underbite.)

Occlusion: Surface to surface contact between opposing teeth, normally measured in percentage.  (Also see, Malocclusion, Simultaneous occlusion.)

Overbite: A situation where the incisors do not meet. A complete malocclusion of the incisors. Protrusion of the upper incisors.  (Also see, Underbite.)

Overjet: Partial displacement of the margins of the incisor teeth, front to back. Partial overlay of the incisor teeth contributes to malocclusions of the incisors. An overjet is where you have partial displacement of the superior incisors in an anterior mode.  (Also see, Underjet.)

Parrot Mouth: (See Overbite.)

Premolars: The first four teeth in each row or arcade of cheek teeth. These teeth are either deciduous or permanent premolars. The wolf tooth is regarded as the first premolar.  (Also see, Molar.)

Protuberant: Something bulging out or higher than the surrounding surface. In equine dentistry, it is usually a high area of an erupting tooth.

Quidding: The carrying of a cud or quid of grass or roughage in the mouth; chewing grass without swallowing it, as with the chewing of gum. Horses often expel quids for fear they would not pass the bowels; horses with poor occlusion are prone to quidding.

Ramp: Pertaining to the excess elongation of the rostral aspect of the number 6 teeth and the caudal portion of the number 11 teeth. A ramped (ski jump) like appearance of a molar, can occur at front or back, upper or lower molar. In occlusion with opposite pathology. A malocclusion.  (Also see, Hook.)

Simultaneous occlusion: The meeting of two occlusive plains, throughout opposing arcades, distributing pressure evenly throughout as many functional teeth as possible during mastication.  (Also see, Occlusion, Malocclusion.)

Supernumerary: An extra tooth that is not a normal part of the dentition.

Underbite: A situation where the incisors do not meet. A complete malocclusion of the incisors. A complete displacement or lack of contact of the inferior incisors in an anterior mode.  (Also see, Overbite.)

Underjet: Partial displacement of the margins of the incisor teeth, front to back. Partial overlay of the incisor teeth contributes to malocclusions of the incisors. An underjet is where you have partial displacement of the inferior incisors in an anterior mode.  (Also see, Overjet.)

Vestigial/vestige: Relating to the remnant of a structure that functioned in a previous stage of species or individual development.

Wolf teeth: Vestigial premolars seen in some equines.  Usually located anterior to the #6 premolars.  Extraction of the wolf teeth is routinely performed to prevent interference with the bit.