Basic Tooth Cusps

tooth cusps

The main cusps of mammalian cheek teeth have specific names used for description. In the diagram, anterior is to the left. Buccal, or lingual, is medial (tongue side) and labial (lip) is lateral. For further orientation purposes, the lower teeth have the suffix "id" (e.g., protoconid is a lower-tooth cusp). The protocone is lingual and the protoconid is labial (so the protocone is "up and in" whereas the protoconid is "down and out"). The sketch to the left upper is of a tribosphenic tooth: a primitive type from which modern mammalian teeth are derived. The lower part of the diagram shows more or less typical squared-up molars of an herbivore derived from the tribosphenic type by the addition of a hypocone on the upper molar and loss of the paracone on the lower.

In the sketches below, brachyodont and hypsodont teeth are contrasted and examples of simple bunodont, selenodont, and lophodont molars are shown.

Sketches of crown height and cusp types rule

Last Update: 11 Jan 2008

Centennial Museum and Department of Biological Sciences, The University of Texas at El Paso