ABSTRACT
<p><b>OBJECTIVE</b>To analyze the stress distribution of temporomandibular joint (TMJ) in posterior cross-bite of individual teeth and in normal occlusion during the intercuspal occlusion (ICO).</p><p><b>METHODS</b>On the basis of the geometric TMJ model of normal occlusion, the TMJ finite element model of posterior cross-bite of individual teeth was reconstructed. The occlusal force and boundary conditions were applied on the model. Using three-dimensional finite element method (FEM), the stress distribution of TMJ in posterior cross-bite of individual teeth was analyzed by simulating the ICO load.</p><p><b>RESULTS</b>No significant differences were found in stress distribution in various TMJ structures between posterior cross-bite of individual teeth and normal occlusion. However, the stress level was higher and the stress distribution was more inhomogeneous in posterior cross-bite of individual teeth than in normal occlusion. In the cross-bite malocclusion of individual posterior teeth, the maximum of von Mises stress was 0.792 MPa, the maximum principal stress was 0.598 MPa and the minimum principal stress was -0.744 MPa. But in normal occlusion, the maximum of von Mises stress was 0.592 MPa, the maximum principal stress was 0.395 MPa and the minimum principal stress was -0.554 MPa.</p><p><b>CONCLUSIONS</b>When the ICO load was applied, the stress distribution of TMJ was more inhomogeneous and the stress level was higher in posterior cross-bite of individual teeth than in normal occlusion.</p>