Introduction: Simultaneous two-jaw surgery is a common procedure performed for the correction of dentofacial deformity patients in Korea, and its effect and stability has somewhat become accepted currently. TOVRO (Transoral Vertical Ramus Osteotomy) or SSRO (Sagittal Split Ramus Osetotomy) is representatively performed with Lefort-I osteotomy in simultaneous two-jaw surgery for mandibular prognathism, but both are definitely different in surgical technique, fixation methods, post-operative complications and prognosis. Even though many operative techniques have been used for the correction of mandibular prognathism, post surgical relapse is still under discussion. The aim of this study is to investigate the long-term stability of Lefort-I + TOVRO for correction of mandibular prognathic patients.

Materials and methods: Forty-six mandibular prognathic patients were treated by simultaneous two-jaw surgery with Lefort-I + bilateral TOVRO, and had cephalometric radiographs taken preoperatively (T0) and immediately postoperatively (T1), and after 2-year postoperatively (T2). All patients were selected under strict criteria for this study.

Results: The mean surgical setback of the pogonion was 11.5 ± 4.9 mm in horizontal direction and 3.2 ± 3.2 mm upward in vertical direction. The mean long-term change was about 1.0 ± 2.3 mm in backward direction and 0.6 ± 1.1 mm in upward direction. There was statistically significant movement in horizontal and vertical direction using PASW 18.0 version, even though the amount was small.

Conclusion: The long-term stability of our present study suggested that simultaneous two-jaw surgery with Lefort-I + TOVRO is very stable procedure for correction of mandibular prognathism.

Conflict of interest: None declared.