Is There a Difference in Condyle Position Changing Pattern Between Deviated and Non-Deviated Sides After Intraoral Vertical Ramus Osteotomy in Facial Asymmetry?

Abstract

The position changing pattern of the condyles after intraoral vertical ramus osteotomy (IVRO) on the deviated and non-deviated sides is not clearly known. This study was conducted to evaluate the changes in condylar position after IVRO in patients with facial asymmetry and to compare the deviated and non-deviated sides using computed tomography imaging. This retrospective cohort study investigated patients with a diagnosis of mandibular prognathism with facial asymmetry who had undergone bilateral IVRO with Le Fort I osteotomy. Condylar positions were recorded on the non-deviated and deviated sides in the midaxial, midsagittal, and coronal planes at 3 time points using 3-dimensional analysis software: preoperatively (T1), at 6months postoperatively (T2), and at 12months postoperatively (T3). Linear and angular changes in condyle position were measured and analyzed between T1, T2, and T3. Reliability and comparative analyses were conducted. Thirty-two patients were involved in this study. At T2, the most superior point of the condyle moved to 1.15±0.24mm (inferiorly) and 0.88±0.23mm (anteriorly) on the deviated side (P=.0002 and P=.0005, respectively) and to 0.99±0.25mm (inferiorly) and 1.08±0.34mm (anteriorly) on the non-deviated side, showing significant differences (P<.0001 and P=.0007, respectively) compared with T1. The condyle position showed a tendency to recover to its original position by T3. However, there were no statistically significant differences between T2 and T3 (P>.05). Furthermore, there were no statistically significant differences between the deviated and non-deviated sides over the entire follow-up period (P>.05). The condyles did not completely recover to their preoperative positions until 12months postoperatively. There was no significant difference between the deviated and non-deviated sides in mandibular prognathism with facial asymmetry.