[Functional remodeling of the mandibular condylar process after bimaxillary orthognathic surgery in patients with skeletal class III malocclusion].

Abstract

Objective: To evaluate morphological changes in the mandibular condyle (MC) during its remodeling following bimaxillary orthognathic surgery in patients with skeletal class III malocclusion.

Material and methods: İn this study 32 three-dimensional virtual models of the condylar process of the mandible from 16 patients with skeletal class III malocclusion have been analyzed. The models were generated from computed tomography scans performed one week before (T₁) and 12 months after (T₂) bimaxillary orthognathic surgery. The analysis included a comparison of MC volumes between T₁ and T₂, as well as T₁-T₂ distance measurements on the apexes of five surfaces (superior, anterior, posterior, medial, and lateral). The relationship between changes in MC volumes and the surgical intervention characteristics (maxillomandibular advancement (MMA) and the degree of mandibular occlusal plane rotation (CCWR)) was also assessed.

Results: The mean MC volume before surgery was 2142.13±427.88 mm³ (95% CI 1987.86 mm³ to 2296.39 mm³), and after surgery, it was 2141.53±540.51 mm³ (95% CI 1946.66 mm³ to 2336.41 mm³). No significant differences were found between MC volumes before and after surgery (T-test=0.0103; p=0.9918; Wilcoxon test=251.0; p=0.8177). T₁-T₂ changes demonstrated minimal remodeling across all MC surfaces, with no significant differences observed between surface pairs (M_T1-T2=0.02±0.38 mm, Kruskal-Wallis test=0.523, p=0.971; ANOVA =0.294, p=0.882). No correlations were identified between changes in MC volume and the characteristics of surgical intervention (r=-0.026 (p=0.888) for MMA, r=-0.07 (p=0.704) for CCWR). Clinically significant symptoms in the temporomandibular joint (TMJ) or instability in mandibular position at T₂ were not observed.

Conclusion: Morphological changes in the MC following bimaxillary orthognathic surgery in patients with skeletal Class III malocclusion fall within the parameters of functional remodeling. These changes are accompanied by mandibular stability and do not lead to TMJ dysfunction in the late postoperative period.