"Orrorin" had small teeth relative to its body size. Its dentition differs from that found in "Australopithecus" in that its cheek teeth are smaller and less elongated mesiodistally and from "Ardipithecus" in that its enamel is thicker. The dentition differs from both these species in the presence of a mesial groove on the upper canines. The canines are ape-like but reduced, like those found in Miocene apes and female chimpanzees. "Orrorin" had small post-canines and was microdont, like modern humans, whereas robust australopithecines were megadont.