Stress analysis of the human temporomandibular joint

Stress analysis of the human temporomandibular joint (TMJ) consisting of ma ndibular disc, condyle and fossa-eminence complex during normal sagittal ja w closure was performed using non-linear finite element analysis (FEA). The geometry of the TMJ was obtained from magnetic resonance imaging (MRI). Th e tissue proportion was measured from a cadaver TMJ. Contact surfaces were defined to represent the interaction between the mandibular disc and the co ndyle, and between the mandibular disc and the fossa-eminence complex so th at finite sliding was allowed between contact bodies. Stresses in the TMJ c omponents (disc, condyle and fossa-eminence complex), and forces in capsula r ligaments were obtained. The results demonstrated that, with the given co ndylar displacement, the stress in the condyle was dominantly compressive a nd in the fossa-eminence complex was dominantly tensile. The cancellous bon e was shielded by the shell shaped cortical bone from the external loading. The results illustrate the stress distributions in the TMJ during a normal jaw closure. (C) 1998 IPEM. Published by Elsevier Science Ltd. All rights reserved.