Diet, dental reduction, and facial reduction

Compend Contin Educ Dent. 2009 Jun;30(5):292-300.

Origins of dental crowding and malocclusions: an anthropological perspective.

Eose JC, Roblee RD.

The study of ancient Egyptian skeletons from Amarna, Egypt reveals extensive tooth wear but very little dental crowding, unlike in modern Americans. In the early 20th century, Percy Raymond Begg focused his research on extreme tooth wear coincident with traditional diets to justify teeth removal during orthodontic treatment. Anthropologists studying skeletons that were excavated along the Nile Valley in Egypt and the Sudan have demonstrated reductions in tooth size and changes in the face, including decreased robustness associated with the development of agriculture, but without any increase in the frequency of dental crowding and malocclusion. For thousands of years, facial and dental reduction stayed in step, more or less. These analyses suggest it was not the reduction in tooth wear that increased crowding and malocclusion, but rather the tremendous reduction in the forces of mastication, which produced this extreme tooth wear and the subsequent reduced jaw involvement. Thus, as modern food preparation techniques spread throughout the world during the 19th century, so did dental crowding. This research provides support for the development of orthodontic therapies that increase jaw dimensions rather than the use of tooth removal to relieve crowding.

2 comments:

Pseudothyrum said...

You might be interested to read or browse the following book - http://journeytoforever.org/farm_library/price/pricetoc.html - which was written by an 'anthropological dentist' back in the 1930s that comes to the same conclusions as this post.

Tod said...

Dental crowding in a prehistoric population
"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)."

Visualization of the shape regression on 2D : 4D ratio (averaged among both hands) within males.

Aggression written in the shape of a man's face