Cingulid

A cingulid is a term used when describing teeth, it refers to a ridge that runs around the base of the crown of a lower tooth (the equivalent on the upper teeth is the cingulum). The presence or absence of a cingulid is often a diagnostic feature for different species of animal, especially among mammals.

Some animals don't have a cingulid. Those that do may have them on only some, or all of the teeth, though most often on the molar teeth. It can be on the upper or lower teeth, or both. There are four common descriptions of the position of the cingulid:

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