Cone-Beam Computed Tomography Evaluation of the Mandibular Condyle and Articular Spaces Following Orthognathic Surgery Using Freehand Articulation Method in Patients With Class II and III Skeletal Deformity.

Objective

This study aimed to assess the changes in the position and size of articular spaces and anteroposterior and mediolateral condyle dimensions following orthognathic surgery. Additionally, it evaluated the correlation between these changes and mandibular movement during surgery.

Methods

This experimental study examined 31 patients (16 with Class III and 15 with Class II malocclusions) who were candidates for orthognathic surgery. Bimaxillary orthognathic surgery was performed on 23 patients, while monomaxillary orthognathic surgery (mandible) was performed on 8 patients. Condyle positioning was achieved using the classic method. In pre- and postsurgical cone beam computed tomography (CBCT) scans, the anteroposterior and mediolateral dimensions of the condyle and spaces and the intercondylar angle were measured. The results were analyzed using the Wilcoxon signed-rank test, with a p-value of less than 0.05 considered significant.

Results

The medial and lateral condyle dimensions and the upper articular space did not change significantly after orthognathic surgery in both Class II and III groups. However, the posterior articular space dimensions showed a statistically significant reduction in both groups. Although the anterior articular space dimensions increased in both groups, this increase was significant only in the Class II group. Additionally, there was a significant relationship between the extent of mandibular advancement or setback and changes in both groups' anterior and posterior articular space dimensions and the upper articular space dimensions in the Class II group.

Conclusion

The classic method for condyle positioning is a suitable approach for orthognathic surgery. The most notable changes were observed in the anterior and posterior articular spaces, likely due to the backward force applied to the proximal part during the fixation stage. According to the evaluations and Spearman's rho, the likelihood of changes in anterior and posterior articular space dimensions increases with more significant advancement and setback.