Evaluation of the resistance of the mandibular condylar region against traumatic forces after coronoidectomy using the finite element method

Aim: The aim of this study is to evaluate the biomechanical changes in the resistance of the mandibular condylar region against traumatic forces following coronoidectomy using the finite element analysis method. Furthermore, the effects of coronoidectomy on the biomechanical balance of the mandible, particularly in terms of stress distribution within the condylar region, were examined in detail. Materials and Methods: In this study, two detailed mandibular models were constructed based on mandibular geometry obtained from a standard anatomical atlas: An anatomically intact control model and a unilateral coronoidectomy model in which the coronoid process was surgically removed. Atlas-derived mandibular data were transferred into the digital environment in high-resolution STL format, and cortical–cancellous bone differentiation, teeth, and periodontal ligament tissues were individually defined to create a heterogeneous and anatomically realistic structure. Both models were evaluated under three traumatic loading scenarios of 2000 N applied to the symphysis, parasymphysis, and angulus regions. Analyses were performed using linear static finite element methods in Abaqus, and changes in Von Mises, Pmax, and Pmin stress distributions as well as deviations in load-transfer vectors were examined in detail. Results: In the coronoidectomy model, all loading scenarios produced marked stress increases in the condylar neck and the ramus–condyle transition zone. Under frontal loading, Von Mises stress rose from 149→210 MPa, with concurrent elevations in Pmax and Pmin causing stress isobands to compress into a narrower region. Oblique loading increased Von Mises from 185→242 MPa and generated a distinctly asymmetric distribution, as the loss of the temporalis force vector redirected load transfer along a steeper path toward the condylar neck. Lateral loading produced the highest amplification, with Von Mises increasing from 380→435 MPa and stress fields collapsing from broad surfaces into a concentrated condylar zone, where both tensile (Pmax) and compressive (Pmin) components intensified along the same anatomical line. Across all models, the shift in shear-stress orientation and sharpening of stress gradients indicated that removal of the coronoid process disrupts load-dissipation pathways, redirecting forces through a shorter, more concentrated biomechanical route toward the condylar neck. Conclusion: Removal of the coronoid process compromises the biomechanical integrity of the ramus-condyle complex by narrowing load-bearing pathways and generating concentrated stress fields in the condylar neck. These findings underscore the coronoid process as a key structural modulator of mandibular load dissipation. Keywords: Coronoidectomy, Mandibular Condyle, Finite Element Analysis.