Effects of Mandibular Asymmetry Correction on Lateral Pterygoid Muscle Volume and Condylar Position: A Retrospective Study.

Abstract

This study aimed to assess alterations in lateral pterygoid muscle volume (LPMV) and condyle position after the correction of mandibular asymmetry by sagittal split ramus osteotomy (SSRO). The data were evaluated by superimposing cone-beam computed tomography (CBCT) images acquired before and after the SSRO. In total, 32 patients were divided into symmetric and asymmetric according to linear measurements from the dental midline. The study variables were lateral pterygoid muscle volume and condylar axial angle (CAA), and measurements were conducted using 3D Slicer software. The study's statistical analysis was performed using ANOVA, Kruskal-Wallis, and Bonferroni post hoc. LPMV exhibited a statistically significant increase in the control (Cs), deviation (Ds), and contralateral sides (CLs) (p = 0.001, 0.001, 0.001, respectively), with the greatest difference in change rate observed in the Ds (p < 0.01). CAA remained unchanged in the Cs (p = 0.147) and CLs (p = 0.509) but demonstrated increases in the Ds (p = 0.008). The study findings revealed significant changes in condyle position and LPMV following SSRO treatment. These alterations suggest a significant impact on the biomechanical environment of the temporomandibular joint and surrounding musculature. Such insights are crucial for understanding the functional outcomes and long-term stability of SSRO treatment in mandibular asymmetry patients.