Biology of Human Dentition - Comparative and Descriptive Anatomy

Vocabulary flashcards covering comparative and descriptive dental anatomy, tooth classifications, surfaces, angles, division of thirds, anatomical landmarks, geometric crown shapes, and interproximal relationships.

Homodont

Dentition in which all teeth are similar in size and shape, such as the dentition of a dolphin.

Heterodont

Dentition in which teeth differ in appearance and shape along the dental arch, such as the dentition of a fox.

Monophyodont

Having only one set of teeth throughout life, as seen in the Beluga whale.

Diphyodont

Having two sets of teeth throughout life, consisting of primary and permanent dentition as in humans.

Polyphyodont

Having multiple generations or sets of tooth replacement throughout life, where lost teeth are continuously replaced.

Thecodont

Teeth that set in sockets with the periodontal ligament, which is the group to which human dentition belongs.

Acrodont

Teeth attached to the top of the jaw bone or in shallow sockets.

Pleurodont

Teeth that sit on a shelf on the inner side of the jaw bone.

Facial Surface

Tooth surfaces oriented toward the face, divided into labial and buccal surfaces.

Labial Surface

Surfaces toward the lip, applicable only to anterior teeth (incisors and canines).

Buccal Surface

Surfaces towards the cheeks, found in posterior teeth (premolars and molars).

Lingual Surface

Surfaces oriented toward the tongue.

Palatal Surface

An alternative term used specifically for the upper arch because of its close contact with the hard palate.

Proximal Surface

Tooth surface facing toward adjoining teeth in the same dental arch, divided into mesial and distal surfaces.

Mesial Surface

Proximal surface faced toward the median line.

Distal Surface

Proximal surface faced distant from the median line.

Occlusal Surface

Surfaces of the premolars and molars that come in contact with the opposite jaw during the act of closure, found only in posterior teeth.

Incisal Surface

Surfaces of the incisors and canines that come in contact with the opposite jaw during the act of closure, applicable only to anterior teeth.

Line Angle

An angle formed by the junction of 2 tooth surfaces. Anterior teeth have 6 line angles and posterior teeth have 8 line angles.

Point Angle

An angle formed by the junction of 3 tooth surfaces. Both anterior and posterior teeth have 4 point angles.

Lobe

Represents a primary center of formation of the tooth; developmental portions that contribute to the formation of the crown.

Cusp

An elevation or mound on the crown of a tooth that makes up a divisional part of the occlusal surface, commonly found on premolars and molars.

Mamelons

Three rounded protuberances found on the incisal ridges of newly erupted incisors, which usually become less noticeable due to attrition.

Tubercle

A smaller elevation on some portion of the crown produced by an extra formation of enamel, considered a deviation from typical form or a mini cusp.

Cingulum

The lingual lobe of an anterior tooth located in the cervical third of the lingual surface, derived from the Latin word meaning girdle.

Marginal Ridge

Rounded borders of enamel that form the mesial and distal margins of the occlusal surfaces of posterior teeth and lingual surfaces of anterior teeth.

Incisal Ridge

The rounded ridge of the incisal portion of an anterior tooth that forms the cutting edge.

Triangular Ridge

Ridges that descend from the tips of the cusps of molars and premolars toward the central part of the occlusal surface, named because their cross-section resembles a triangle.

Transverse Ridge

A combination of two triangular ridges that transversely cross the occlusal surface of a tooth.

Oblique Ridge

A ridge characteristic of maxillary molars that crosses obliquely across the occlusal surface, formed by the union of the triangular ridge of the distobuccal cusp and distal cusp ridge of the mesiolingual cusp.

Cusp Ridge

Elevations that extend from cusp tips in mesial and distal directions, or buccal and lingual directions.

Inclined Plane

A sloping area found between two cusp ridges.

Fossa

An irregular depression or concavity on the crown of a tooth.

Lingual Fossa

A broad, shallow depression on the lingual surface of anterior teeth.

Central Fossa

A broad and deep concavity at the central portion of the occlusal surfaces of molars.

Triangular Fossa

A fossa found on occlusal surfaces of premolars and molars located between branches of the central developmental groove when they terminate before proximal marginal ridges.

Sulcus

An elongated valley formed by the inclines of adjacent cusps or ridges that meet at an angle.

Groove

A shallow linear depression on the tooth surface.

Developmental Groove

A shallow groove or line between primary parts of the crown or root that indicates the junction between primary developmental parts.

Supplemental Groove

A less distinct, shallow linear depression on the surface of a tooth that does NOT mark the junction of primary parts.

Pit

A small pinpoint depression located at the junction of developmental grooves or at the terminal ends of those grooves.

Contact Area

Areas on the proximal surface of the teeth where adjacent teeth touch one another in the same arch.

Interproximal Space

Triangular spaces between the teeth formed by bone on one side and proximal surfaces and contact area on the other side, normally filled with interdental papilla.

Embrasures

Spillways formed by spaces between teeth where they diverge buccally, labially, lingually, and occlusally from the contact area.

Height of Contour

The crest of curvature representing the highest point of elevation on a tooth surface.