1Organismal Biology & Anatomy, University of Chicago, 2Department of Community and Family Medicine, Duke University, 3Pritzker School of Medicine, University of Chicago
Thursday Afternoon, 200DE
Foods of different material properties elicit different feeding behaviors. How those behaviors impact mandible morphology depends on their associated patterns of stress and strain. Patterns of strain in the Cebus mandible were investigated using a finite element model (2.5 million tetrahedral elements) constructed from high-resolution CT scans. Material properties were assigned to trabecular bone, periodontal ligament, and teeth, and to 36 regions of the cortical bone of the mandible. Applied muscle forces were calculated from the PCSAs of the temporalis, superficial and deep masseters, and medial pterygoid muscles from the same individual. The models were constrained at single nodes at the center of each jaw joint: one model was also constrained at the right premolars, a second model on the first, second and third molars. The models were solved using the linear static solver in Strand7 and contour plots of von Mises strain compared under the two loading conditions. Under both models high strains are seen on the condylar heads and necks and on the buccal aspect of the corpus below the molars on both working and balancing sides: in the premolar biting model strain magnitudes are higher at these locations. The molar constrained model experienced higher strains on the lingual aspect of the symphysis and working side corpus. These results suggest that under different feeding behaviors may be reflected in differences in symphysis and corpus morphology.
Funded by an NSF HOMINID Grant BCS 0725126.