Shkurkin G V, Almquist A J, Pfeihofer A A, Stoddard E L
J Dent Res. 1975 Mar-Apr;54(2):402-6.
Scanning electron micrographs were taken of sets of human molars-those of paleo-Indians used in mastication of, ostensibly, a highly abrasive diet, and those of contemporary Americans. Different ultrastructural patterns of enamel wear were observed between the groups.