Evaluation of Skeletal Class III Malocclusion Patients Treated With BSSRO in Surgery-first Approach
Purpose: Surgical-orthodontic treatment that eliminates or minimizes presurgical orthodontics, known as Surgery First Approach(SFA), has lately been gaining popularity in East Asian countries. However, its efficacy has yet been thoroughly proven in the literature. The purpose of this study is to evaluate treatment results of skeletal class III malocclusion patients treated with BSSRO in SFA.
Patients and methods: 30 skeletal class III patients who had BSSRO in SFA were included in the study. Lateral cephalometric radiography was taken preoperatively and 1 month and 6 month postoperatively. Pogonion(Pog) and B point(B) were marked as skeletal landmarks and soft tissue pogonion(Pog’), soft tissue B point(B’) and Lower lip(LL) were marked as soft tissue landmarks. Overjet, overbite and lower incisor axis angle(L1 axis) were measured to assess dental relationship. To test for significance between measurements from each time period, a repeated-measured analysis of variance (ANOVA) was performed. When significant, post-hoc tests with the Bonferroni correction were done(α=0.05).
Results: Pogonion and B point showed significant posterior movement in 1 month postsurgery. Vertically, Pogonion moved superiorly after surgery and B point moved superiorly during postoperative orthodontic treatment period. All the soft tissue landmarks moved posteiorly. Overjet and overbite were changed to be within norm. Lower incisor showed labial inclination during postoperative orthodontic treatment period.
Conclusions: After the surgery, all the skeletal and soft tissue landmark measurement changes were coherent with the treatment objectives. Also, the treatment results were stable throughout postoperative orthodontics period. Overjet and overbite were normalized and lower incisor angle were changed to be more labially inclined.
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