Short‑term and long‑term alterations of condylar position after bilateral sagittal split ramus osteotomy for mandibular setback: A preliminary before‑after clinical trial

Abstract

Background: Because of the importance of the condyle, it is crucial to document all changes in its
position after orthognathic surgery. Since previous studies in this regard are mostly controversial
and limited by two‑dimensional radiography technique, this study was conducted.
Materials and Methods: This prospective clinical trial was performed on 102
measurements (17 patients, 2 condyles each, and 3 time points). Cone‑beam computerized
tomography imaging was done for 17 skeletal Class‑III patients (10 females and 7 males, mean
age, 24.05 ± 4.78 years) undergoing fixed orthodontic treatment, at three time points T0 (before
surgery), T1 (immediately after surgery), and T2 (8 months after surgery). Condylar positions were
measured. Position changes were evaluated during the course of the study. They were also compared
between right/left sides and between men and women. Tests in use were repeated‑measures one‑ and
two‑way analysis of variance and paired t‑tests (α =0.05, α =0.017).
Results: Alterations in various anatomical condyle parameters over the 8‑month course of the
study did not reach the level of significance (P ≥ 0.078). At all intervals, mean anterior‑posterior
index (API) remained between −12 and +12 (indicative of central position of the condyle in the
glenoid fossa). Between men and women, left superior joint space, left anterior joint space, and
left API differed (P ≤ 0.05). Left condyle mean superior joint space and anterior joint space were
greater in men compared to women in all the three intervals; left condyle mean API was greater
in women compared to men (more posterior in men, P ≤ 0.05).
Conclusion: Condyles might not change significantly after 8 months post‑surgery. However, small
changes might be observed, and these changes might differ between the left and right sides and
between males and females.
Key Words: Mandibular condyle, orthognathic surgical procedures, sagittal split ramusosteotomy