Research on Biomechanical Behavior of Three-dimensional Bilateral Temporomandibular Disorder Models

Background: The aim of this study was to evaluate the stress distributions of the bilateral temporomandibular disorder (TMD) model during jaw closing and maximum opening. Methods: One symptom-free volunteer group and one symptomatic patient group were selected as the control group (CG) and the TMD group (TG), respectively. To determine the causes of temporomandibular joint (TMJ)-related pain, the magnitude and location of the maximum stresses under physiologic loading were examined. Several finite element TMJ models have been developed in previous studies, but few have used a bilateral mandible model including jaw opening and closing. Four three-dimensional (3D) models were reconstructed, and loading conditions were established for stress analysis using magnetic resonance imaging (MRI). In this study, we analyzed the maximum stress and asymmetry index between the CG and the TG for condyle, disc, and articular eminence using finite element analysis program. Results: Data analysis indicated the condyle was asymmetrical during jaw closing, and the disc was also asymmetrical during jaw opening in the TG. The maximum stresses did not differ significantly between the CG and the TG during jaw closing and opening. Conclusion: The results of our research will provide potential clinical benefits in terms of understanding TMD stress properties during jaw closing and opening.