ALVEOLAR:  
The part of the jaw in which the teeth are set, acting as a shock absorber between tooth and bone.

ALVEOLAR SOCKET:
The socket in which the lower part of the tooth sets.

ANKYLOTIC, ANCHYLOTIC, ANKYLOSIS, ANKYLOSE:
Cemented together, usually by bony substance.

ANTERIOR:
Toward the front of the body.

APICAL:
Pointed; the top of a mountain peak is its apex. In equine dentistry, used to describe the shape of the tip of a tooth root; the area where the nerves and blood vessels enter the root.

APICAL FORAMEN:
The hole in the apex of a tooth root through which the nerves and blood vessels enter.

ARCADES:
The individual rows of teeth.

ACCESSIONAL TEETH:
The permanent molars, so called because they have no deciduous predecessors in the dental arch.

AXIS:
An imaginary line about which a body rotates.

AXIAL FLOW:
The flow of the food around an imaginary centre as it moves rearward through opposing upper and lower batteries of teeth.

BATTERIES, DENTAL BATTERY:
A row of teeth of uniform shape and size, which are so closely spaced, as to make finding their adjacent edges difficult.

BIOMECHANICS:
A compound word formed from the Greek term bio, meaning life + mechanics; the physical principles governing the action of simple machines such as levers and pulleys. Thus, the application of the laws of mechanics to living organisms. Dentistry is especially concerned with the live mechanical action of the mandible or lower jaw working against the stationary upper jaw.

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

BUNODONT: (boo’-no-don’t)
Teeth with separate, cone-shaped cusps such as human cheek teeth.

CANINES:
Conical teeth found between the incisors and cheek teeth. They are variously called “fighting teeth”, “fangs,” “tushes” or “bridle teeth,” and their function is tearing.

CAP:
The remnant of a deciduous tooth, which is shed at a specific time.

CAPITULUM:
A small rounded articular end of a bone.

CARIES:
Decay of a bone or tooth.

CARNASSIAL TOOTH:
A large cheek tooth designed for shearing, found only in carnivores. The upper fourth premolar and lower first molar in dogs and the upper third premolar and lower first molar in cats; also called sectorial tooth.

CEMENT, CEMENTUM:
The SECOND hardest material of the tooth. It enwraps the external enamel of molars and premolars and fills the infundibulae of molars, premolars and incisors.

CHRONIC:
Continuing over a long period of time; prolonged, lingering; in medical terminology, the opposite of acute.

COMMINUTE, COMMINUTION:
To chop or mince.

COMMISSURE:
A site of union of corresponding parts, as the angle of the lips or eyelids.

COLIC:
Spasm in any hollow or tubular soft organ accompanied by pain.

CONGENTIAL:
Existing before birth, occurring during fetal life; hereditary.

CURVE OF SPEE:
The dorso-ventral curvature of the upper and lower jawbones and dental arcades.

DECAY:
Decomposition of organic matter by the action of micro organisms.

DECIDUOUS:
Falling off or shedding, which occurs seasonally or at a certain stage of development in the life cycle.

DENTIN OR DENTINE: (den’-tinn)
The SOFTEST substance of which teeth are composed; forms the body of the tooth and cusps and fills the pulp cavity.

DIASTEMA:
A space between teeth, in the horse, the area between the incisors and premolars; the interdental space of the bars where the bit lies.

DISTAL:
Direction away from the “core” of the animal’s body. Usually used to describe limbs or long body structures. Examples: the horse’s hoof is distal to its shoulder; the top of the horse’s tongue is distal to its root. Opposite of proximal.

DORSAL:
Anatomically above or toward the backbone or back. Examples: the horse’s withers are dorsal to its breast; the orbits are dorsal to the angles of the jaw.

DUCT:
A tube.

ECTOPIC TOOTH:
A tooth occurring in a body part other than the alveolus.

ENAMEL:
The HARDEST material of which teeth are composed. In bunodont teeth, the enamel coats the cusps and whole occlusal surface of the tooth as icing coats a cupcake. In lophodont teeth such as those of the horse, except in a newly erupted tooth, the enamel is visible on the occlusal surface as thin bands forming loop-shaped patterns.

ENDOSTEUM:
The vascular membrane lining the medullary cavity of a bone.

ENDOSTOSIS:
Bone formation beginning in the substance of cartilage.

EPITHELIUM & ENDOTHELIUM
Lining tissue. “Epi” means “around” or “on the outside of” and “endo” means “on the inside of.”

ERUPTION:
When talking of horses’ teeth, eruption means the rate at which the crown protrudes above the gum line; the rate of eruption is adjusted to match the rate of wear of the grinding surface of the teeth.

FACIES: (Latin for “face” or “surface”)

FACIES MASTICATORIA:
Referring to the grinding or occlusal surface of the tooth.

FACIES LABIALIS:
Referring to any surface within the mouth facing the lips, or externally, the front of the snout or muzzle.

FACIES BUCCALSI:
Referring to any surface within the mouth facing the cheeks, or externally, the cheek or side of the head.

FACIES LINGUALIS:
Referring to any surface within the mouth facing or in contact with the tongue.

FACIES CONTACTUS:
Referring to the plane of occlusion of the arcades or the surfaces along which the teeth meet.

FECES, FECAL SAMPLE:
Excretion from the bowels, waste products from the horse, manure; we check a faecal sample to see if all the particles of roughage and grain are well-ground as a way of determining whether the teeth are working properly.

FISSURE:
A thin crack or split; in horse’s teeth, often a self-induced or practitioner-induced vertical crack in a molar.

FISTULA:
A duct or canal formed by the imperfect closing of a wound, abscess, or the like and leading either from the body surface or from one body cavity or hollow organ to another.

FORAMEN:
Anatomically, a round opening or hole.

FOSSA:
Anatomically, a recess, cup, or groove.

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.

GINGIVAL: –(jin’ji-val)
Of or pertaining to the gums.

GINGIVITIS:
Inflammation of the gums.

GLENOID:
Having the appearance of a socket.

GUM:
Oral mucous membrane; the firm, fleshy tissue covering the alveolar parts of either jaw and enveloping the necks of the teeth.

HOOK:
As used in equine dentistry, a pointed end or peak developed on a tooth through abnormal wear.

IMPACTED TEETH:
Teeth, which have been prevented from erupting by some mechanical obstacle. Obstacles deprive teeth of the room they need to erupt properly. Impactions often create secondary reactions in alveoli or jaws, may be diagnosed either by observation, palpation, or X-ray, and may require extraction or other surgery to correct.

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

INFERIOR:
Referring to that which is below or lower. Example: the mandible is the horses’ inferior jawbone.

INFUNDIBULUM: (plural, infundibulae)
The tube-like spaces found in the centres of both incisor and cheek teeth. In horses, the infundibulae are filled, or nearly filled, with cementum. The infundibulum of an incisor is single and is called the “mark,” “spot,” or “cup”. The infundibulae of premolars and molars are double and form the hollow cylindrical tubes running vertically down the tooth, which are visible especially after a cap is removed.

INSIDIOUS:
Stealthy, treacherous, hidden: not apparent, as a disease that does not exhibit symptoms of its onset or progress.

INSTRUMENT:
A tool or piece of apparatus; in equine dentistry, a piece of equipment used to examine, correct, compensate or equilibrate the dentition.

LABIAL: (lay’-bi-al)
Of or pertaining to the lips; also, as a direction, toward the lips.

LOPH, LOPHODONT:
Primitively, the bodies of teeth are organized into separate, cone-shaped cusps. Through evolution of the horse family, rows of cusps become confluent to form lophs. Lophodont teeth are formed of or characterized by lophs.

MALOCCLUSION:
In horses’ teeth, the inability of the arcades of molars or incisors to occlude or fit together properly.

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

MANDIBULAR:
Pertaining to the lower jaw; the moving part of the skull that affects grinding or mastication.

MASTICATION:
The grinding or comminution of the food by the teeth.

MECHANICAL:
Referring to a machine, such as the bit or any type of tack applied to the horse; or to the action of for example the jaws with respect to their leverage, to the forces, which they can exert, or to their mode of action.

MEDIAL: (mee’-dee’al)
Toward the midline or sagittal plane of the body, or toward the midline of a given limb. Example: the horses’ forelock is medial to its left ear; the cleft of the frog is medial to the wall of the hoof; the inner wall of the hoof is medial to the outer wall of the hoof. Compare to mesial.

MESIAL: (mee’-zi’al)
Toward the middle or center. Examples: the central incisors are mesial to the lateral incisors; the fourth premolar is mesial to the second premolar; the cleft of the frog is mesial to the walls of the hoof. Compare to medial.

MAXILLA: (mak’-sil-ah)
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” work.

MAXILLARY:
Of or pertaining to the maxilla.

MEDULLARY: (med’-ewe-lair-y)
The centre or core of a structure such as brain, kidney, tooth, etc.

MOLAR:
One of the accessional or permanent teeth. Molars have no deciduous predecessors in the dental arcades.

MUCOUS MEMBRANE:
Epithelial tissue richly supplied with cells, which can secrete mucus. Lines not only the mouth but other body orifices such as anus, vagina, eyelids, nostrils, etc. (mucus membrane)

OCCLUDE:
In dentistry indicates surface-to-surface contact; to meet closely or fit into each other, as opposing teeth in the upper and lower jaw.

OCCLUSION:
Surface to surface contact between opposing teeth.

ODOR:
The quality of a substance, which renders it perceptible to sense of smell.

OSSIFY, OSSIFYING, OSSIFICATION:
To convert into bone, to harden like bone.

PALATE:
The roof of the mouth.

PALATABLE:
Agreeable to the “palate”; tasty.

PALATINE ARTERY:
The large artery that lies just inside the upper arcades of molars in the soft tissues forming the roof of the mouth.

PERIOSTEUM:
The tough elastic membrane covering the surface of bone shafts; its function is to protect the bone, support blood vessels and nerves, and provide a source for cells, which engender growth at the bone surface.

PERIOSTITUS:
Inflammation of the periosteum.

PERIODONTAL LIGAMENTS:
Tough, short fibres which secure the neck of the tooth to the rim of the alveolus; which perform like shock absorbers to dampen occlusal pressures; from which arise cells producing cementum. Chronic tension on periodontal ligament fibres from pressure or loosening of the tooth in the socket may induce formation of excessive cementum, ankylosing tooth and alveolus.

PERIODONTAL:
Literally in Latin “around or near the teeth”; usually used to refer to gums or other soft tissues of the mouth.

PERIODONTITIS:
Inflammation of tissues surrounding a tooth.

POSTERIOR:
Behind or toward the hinder part; coming after another in a series.

PREMOLARS:
The first three teeth in each arcade or row of cheek teeth. These teeth are either baby teeth (i.e.: caps) or permanent premolars.

PROGNATHOUS, PROGNATHISM:
Protrusive snout or protruding jaw, either upper or lower.

PROPHYLAXIS, PROPHYLACTIC:
Preventive care. In horse dentistry, this means regular dental maintenance.

PROTUBERANCE, PROTUBERANT:
Bulging out beyond the surrounding surface.

PULP CHAMBER/PULP CAVATIES:
Cavities in the central, lower portion of horse teeth which house nerves and blood vessels that gives vitality to the tooth.

PUTRIFACTION:
The process of organic decomposition.

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

RASPING TEETH – FLOATING TEETH – RUBBING TEETH – EQUILIBRATING TEETH:
The methods used to remove the buccal/lingual edges of the arcades along with protuberant portions of the surface of cheek teeth and incisors in an effort to create more perfect occlusion and maximum lateral excursion.

ROOT:
Invisible part of the tooth, the part that lies below the gingival or gum in human teeth; in horses the root starts at the base of the reserve crown where the enamel folds cease.

ROOT CANAL:
The pulp chamber of the tooth.

ROSTRAL:
Toward the front of the mouth; toward the snout; anatomically, the anterior portion of the upper jaw structured by the premaxilla bone.

SAGITTAL:
The anatomical plane running down the length of the horses’ body, which splits it into left and right halves. Named for Sagittarius, the mythical archer.

SECTION:
The process of cutting; a division or segment of a part; a surface made by cutting.

SELENODONT:
A tooth structure in which cusps have become confluent to form crescents. Found in cattle and other cloven-hoofed ruminants, this tooth structure functionally parallels the Lophodont characteristic of horses. “Selene” means, “shaped like the crescent moon.”

STAR – DENTAL STAR:
In older texts, the exposed portion of the pulp chamber on the occlusal surface of the incisors; in newer texts, the spot, mark or exposed portion of the open infundibulum on the occlusal surface of the incisors.

SUPERIOR:
Referring to that which is above. Example: the maxilla structures the superior jaw of the horse.

SUPERNUMERARY:
An extra tooth, which is not a normal part of the dentition.

TABLES OF INCISORS:
The nipping or occlusal surface of the incisors.

TEMPORO-:
Combining form meaning temples of the head.

TABLES OF CHEEK TEETH
MOLARS:
The grinding or occlusal surface of the premolars and molars.

TRANSVERSE:
Lying across; crosswise.

TREPHINATION:
Process of cutting out a piece of bone with the trephine.

TREPHINE:
To perforate with a trephine; a cylindrical saw for cutting a circular piece of bone out of a skull.

TUSHES – TUSKS:
The grinding or occlusal surface of the premolars and molars.

VENTRAL:
Anatomically, that which is below or toward the horses’ belly. Example: the horses’ breastbone is ventral to its withers; the mandible is ventral to the maxilla. Opposite of dorsal.

VICE:
A bad habit.