Cephalometric and soft tissue determinants of esthetic outcomes after single-jaw mandibular setback surgery in skeletal class III patients: A retrospective study.

BACKGROUND/PURPOSE: Orthognathic surgery is an effective treatment for skeletal Class III malocclusion; however, the relative influence of skeletal and soft tissue variables on postoperative esthetic outcomes remains unclear. This study aimed to evaluate the relationships among cephalometric parameters, soft tissue changes, and esthetic outcomes following single-jaw mandibular setback surgery.

MATERIALS AND

METHODS

A retrospective study was performed on 258 adult patients with skeletal Class III malocclusion subspinale-nasion-supramentale (ANB) angle <0° who were treated between 2016 and 2021. Patients were divided into three groups: bilateral vertical ramus osteotomy (BVRO) group (n = 99), genioplasty alone group (n = 30), and BVRO plus genioplasty group. (n = 129). Cephalometric and soft tissue variables, including nasolabial angle, lip position relative to the Ricket esthetic line (E line), vertical height, and occlusal plane angle, were evaluated. Statistical analyses included multiple regression and receiver operating characteristic curve (ROC) analysis.

RESULTS

Postoperative esthetic outcomes based on the E line were achieved in approximately 47-50% of patients across groups. Significant improvements in sella turcica-nasion-subspinale (SNA) angle, sella turcica -nasion-supramentale (SNB), sella turcica -nasion-symphysis center (SND), and Wits appraisal were observed (P < 0.05). BVRO demonstrated the greatest mandibular setback (~11 mm). Vertical height change was a significant predictor in females, whereas upper lip position was significant in males in the BVRO plus genioplasty group. ROC analysis showed moderate predictive ability (area under curve (AUC) 0.60-0.67.

CONCLUSION

Both skeletal and soft tissue variables influence esthetic outcomes. A multifactorial evaluation is essential for optimizing surgical planning in skeletal Class III patients.