Introduction: On account of its specific biodynamics, the disc joint located at the very heart of the joint can impact every constituent of the manducatory system. The disc is deformed when subjected to stresses exerted by the muscles of mastication which it partly absorbs and partly redistributes.
Materials and methods: CT-scan slices and MRI images of a subject were made in order to create a finite element anatomical model of the TMJ. The forces applied to the subject's joint model were obtained by performing vector decomposition of the maximum muscle forces produced by this individual. The resultant force in this study was subjected to different frequencies approximating those observed in mastication.
Results: The reaction force at the glenoid fossa can reach up to 1035 N depending on the frequency of the indentation. Generally, during the different exercises, the areas of maximum stress were located at the lateral portion of the disc and on the posterior band. They reached forces up to 13.2 MPa following a 32 s exercise at a frequency of 0.5 Hz.
Discussion: Even if the behavior law needs to be improved, joint resiliency was demonstrated in this study. The areas of maximum stress were equivalent in the different exercises on account of the anatomy of the different parts and the axis of the forces applied. This study offers food for thought regarding joint disorders and opens the way for further research to complement the current investigation.
Copyright © 2012. Published by Elsevier Masson SAS.