Stress Analysis of Anterior-Disc-Displaced Temporomandibular Joint Using Individual Finite Element Model

Abstract

Temporomandibular joint (TMJ) disorder relates to the biomechanical irregularity of the structual joint components, and the behavior of soft tissue components is considered as a key to understand the biomechanical condition in the TMJ. The configuration of joint components, however, closely depends on individual patients. In this study, attention has been focused on the stress and displacement of irregular TMJs with anterior disc displacement. Using biplane magnetic resonance (MR) images, typical anterior-disc-displaced (ADD) TMJ of a patient with temporomandibular disorder has been modeled individually. The stress distribution in ADD TMJs has been compared with that in normal TMJs. Parameter studies with the elastic modulus have been carried out and it revealed that the stress distribution in the TMJ is highly dependent on the connective tissue modulus as well as disc modulus in the case of ADD TMJ, and that the disc displacement due to mouth opening movement depends on disc modulus in normal TMJ but depends on retrodiscal connective tissue in ADD TMJ.