Anomalous development of the upper third premolar in a dog and a cat.

Two cases of anomalous development of the upper third premolar in a dog and a cat are described. The involved teeth have a bifid crown and 3 roots. The central root is abnormally wide and has 2 separate root canals. The anomalous tooth is the cause of malocclusion in the cat and of periodontitis in both cases. The difficulty in distinguishing gemination from fusion is discussed.