Biomechanical Effects of Joint Disc Perforation on the Temporomandibular Joint: A 3D Finite Element Study

Abstract

Background:Disc perforation (DP) is a severe type of Temporomandibular Disorder (TMD). DP may induce changes in the internal stresses of the temporomandibular joint (TMJ). A systematic biomechanical analysis of TMJ DP has not been conducted in previous studies. Herein, this study attempts to investigate the biomechanical effects of different positions and sizes of DP on the TMJ using a biomechanical approach, to explore the mechanical pathogenesis of TMD. Methods: Eleven three-dimensional finite element (FE)models of the TMJ were constructed based on CBCT imaging files of a patient with DP on the left side. These models included the disc with anterior displacement of the affected TMJ and discs with different locations and sizes of perforations on the affected disc. FE methods were conducted on these models. Results: When the discs of both TMJs are in a normal position, the maxim von Mises stress (MVMS) experienced by both joints is comparable, maintaining a state of equilibrium. Anterior displacement of the disc leads to a significant increase in the MVMS in both TMJs, with the affected side exhibiting a more pronounced effect. DP occurring at the posterior band and the junction between the disc and the bilaminar region has a greater impact on the MVMS of both TMJs compared to perforations at other locations. As the size of the perforation increases, both sides of the TMJ discs, including the bilaminar regions and the condyles on the normal side, exhibit an increase in the magnitude of MVMS. Conclusions: Anterior disc displacement and DP have the potential to adversely affect the stress distribution on both sides of the TMJs. Timely management of TMD in the early stages is crucial to prevent disease progression and worsening of symptoms.