Optimizing Fixation in Mandibular Angle Fractures: A Biomechanical Comparison of Single, Double, and 3D Miniplate Systems using Finite Element Analysis

This study evaluates the stress distribution on miniplates and bone and the displacement of fractured segments in mandibular angle fractures using Finite Element Analysis (FEA). Three fixation methods were analyzed: a single straight titanium miniplate on the superior border, two straight titanium miniplates placed on the superior and inferior borders, and a 3D miniplate on the lateral surface. A 3D mandibular model was generated using CT and CBCT imaging, and occlusal forces were applied in a vertically downward direction. Stress distribution was assessed through von Mises stress analysis, and maximum displacement of fracture segments was compared across fixation methods. The results showed that the highest von Mises stress on miniplates was observed in the 3D plate fixation model, reaching 673 MPa at 1000N, exceeding the titanium yield limit, while the single and two-plate models remained within safe limits at 195.17 MPa and 367.1 MPa, respectively. The highest stress on screws and screw holes was also recorded in the 3D plate model, with 415.72 MPa on screws and 52.15 MPa on screw holes, indicating a higher risk of deformation. Total deformation analysis showed that the inferior border exhibited the maximum displacement in all models, with the highest displacement of 0.052 mm observed in the two-plate model. Within the study's limitations, the findings suggest that a single miniplate on the superior border provides adequate stability while being surgically simpler. FEA offers valuable insights into biomechanical behavior, aiding in the optimization of fixation techniques before clinical trials.