Mandibular biomechanics and development of the human chin.
The development of the chin, a feature unique to humans, suggests a close functional linkage between jaw biomechanics and symphyseal architecture. The present study tests the hypothesis that the presence of a chin changes strain patterns in the loaded mandible. Using an anatomically correct 3-D model of a dentate mandible derived from a CT scan image, we analyzed strain patterns during incisal and molar biting. We then constructed a second mandible, without a chin, by 'defeaturing' the first model. Strain patterns of the second model were then compared and contrasted to the first. Our main finding was that chinned and non-chinned mandibles follow closely concordant patterns of strain distribution. The results suggest that the development of the human chin is unrelated to the demands placed on the mandible during function.
Ichim
I
I
Department of Oral Sciences, Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
Swain
M
M
Kieser
J A
JA
D000220:Adaptation, Biological; D000328:Adult; D005075:Biological Evolution; D001696:Biomechanical Phenomena; D001732:Bite Force; D002680:Chin / Q000502:physiology*; D003198:Computer Simulation; D003799:Dental Stress Analysis; D020342:Finite Element Analysis; D006801:Humans; D008334:Mandible / Q000502:physiology*; D008953:Models, Anatomic