Finite element analysis of biomechanical alterations in the temporomandibular joint induced by posterior tooth wear under the centric occlusion.

backgroundPosterior tooth wear is a common clinical finding, yet the biomechanical impact after tooth wear on the temporomandibular joint (TMJ) remains unclear. This finite element analysis (FEA) study aimed to investigate stress alterations within the TMJ articular disc induced by varying patterns of posterior tooth wear under the centric occlusion.

methodsA subject-specific three-dimensional finite element model of the skull, including the TMJs with articular discs, was developed from medical imaging. The models of varying patterns of posterior tooth wear were built to analyze the effects of the number of worn teeth, wear depth, and wear symmetry (symmetric vs. asymmetric) on disc stress. Simulations were performed under static centric occlusion.

resultsThe high stress areas were located notably in the intermediate zones of disc. The results demonstrated that increasing the number and depth of worn teeth led to a progressive elevation in von Mises and minimum principal stresses within the articular disc. Crucially, in asymmetric wear scenarios, the disc on the more worn side sustained higher stress compared to the less worn side, with the stress disparity widening as asymmetry increased.

conclusionsProgressive posterior tooth wear, particularly when asymmetric, significantly increases the biomechanical burden on the TMJ disc. This provides a plausible biomechanical explanation for the clinical observation of ipsilateral TMD symptoms in patients with unilateral tooth wear. The findings underscore the importance of occlusal management in patients with significant tooth wear to mitigate adverse TMJ loading.