Dental crowding in a prehistoric population.

The aims of this study were to investigate dental crowding from the Copper Age and examine the extent and patterns of wear. Crowding was estimated in 43 adult mandibles using Little's irregularity index. Dental wear, dental diameters, arch width and the presence of third molars were also studied as possible aetiological factors for crowding. The remains were found at the archaeological site of Roaix, located in the south of France. Radiocarbon dating indicated that the lower layer was from 2150 +/- 140 years BC (date +/- 1 standard deviation) and the upper level from 2090 +/- 140 years. The graves were estimated to contain the remains of 150 adults and 50 children. Forty-three intact mandibles were used for this study. All of the mandibles presented incisor crowding with a majority of minimal and moderate irregularities, but in seven cases there were extreme irregularities and in two canine impaction was observed. These results are in contrast with the literature where it is reported that malocclusions were rare in prehistoric populations. The findings of this study suggest that crowding may be of a genetic origin and might not be caused by excessive tooth size or changes in environmental factors (masticatory activity).