Skeletal Class III malocclusion due to mandibular prognathism has a substantial impact on facial aesthetics and masticatory function. Bilateral sagittal split osteotomy (BSSO) remains a reliable procedure for mandibular setback; however, early postoperative mandibular stability, particularly at the B-point and pogonion, is still clinically relevant in treatment assessment. This study aimed to evaluate early mandibular skeletal stability by quantifying positional changes at the B-point and pogonion 6 months after an isolated modified BSSO mandibular setback in adult patients with skeletal Class III malocclusion. A retrospective study was conducted in 46 patients who underwent isolated mandibular setback using BSSO. The sample size was determined based on a previous study evaluating mean B-point stability in 46 patients after mandibular setback surgery. Cephalometric measurements were recorded at three time points: before surgery (T0), 10 days after surgery (T1), and 6 months after surgery (T2). Skeletal and dentoalveolar variables were reported as mean ± standard deviation (SD), and paired comparisons were performed for within-subject changes over time. Postoperatively, the mandibular skeletal relationship returned to Class I, with the SNB angle decreasing by an average of 5.90° and the ANB angle increasing significantly (p < 0.05). At the 6-month follow-up, skeletal relapse was not statistically significant (p > 0.05). Mandibular setback via BSSO is an effective method for correcting skeletal relationships in Class III malocclusion. Preliminary results at 6 months show a suggested favourable short-term skeletal stability trend; however, studies with longer follow-up periods are necessary for definitive confirmation.
