Prevalence of malocclusion in medieval and modern Danes contrasted.

A comparison was made of frequencies of anomalies of the dentition, occlusion, and space conditions for the permanent dentition in the skeletal remains of 278 medieval Danes and in 1258 contemporary Danes. The congenital anomalies of the dentition were equally common in the samples. Extreme maxillary overjet and distal molar occlusion, deep bite, and crowding were considerably less frequent in the Middle Ages. The frequencies of mesial molar occlusion and crossbite, but not that of midline displacement, were higher in the medieval sample, especially in the older subjects. It is suggested that the observed differences in malocclusion prevalence were related to exogenous factors, primarily the pronounced dental attrition.