Department of Orthodontics, University of Oslo, Oslo, Norway.
Department of Orthodontics, University of Oslo, Oslo, Norway.
Am J Orthod Dentofacial Orthop. 2020 May;157(5):631-640. doi: 10.1016/j.ajodo.2019.05.018.
The purpose of this study was to compare treatment outcomes for anterior occlusion and vertical skeletal stability after maxillary or mandibular surgery for correction of Class II malocclusion with a mild to moderate open bite.
The records of 57 consecutive patients were retrieved; 30 had undergone 1-piece Le Fort I osteotomy, and 27 had undergone a bilateral sagittal split osteotomy (BSSO), without additional surgery. Lateral cephalograms at 6 stages were available (pretreatment to 3 years postsurgery).
After the surgery, 87% of the Le Fort I patients and 63% of the BSSO patients had a positive overbite, and at the 6-month follow-up, the percentages were 90% and 74%, respectively. At 3 years after surgery, 74% of the Le Fort I patients and 42% of the BSSO patients had a positive overbite. The anterior facial height decreased in the Le Fort I subsample and increased in the BSSO subsample, and the mandibular plane angle decreased in both. The Le Fort I subsample generally remained stable, whereas clinically significant relapse of the mandibular plane angle (≥2°) occurred in 80% of the BSSO subsample.
When taking into account the limitations of retrospective clinical studies, several conclusions can be drawn. A significant improvement of the anterior occlusion can be expected in most patients when either maxillary or mandibular surgery is used for correction of Class II open bite. However, there will be individual patients in whom considerable posttreatment changes occur in both the anteroposterior and vertical dimensions. Although individual morphology needs to be taken into account, it seems that both short- and long-term stability are likely to be greater after Le Fort I surgery compared with BSSO.
本研究的目的是比较上颌或下颌手术治疗 II 类错牙合伴轻中度开牙合畸形的前牙咬合和垂直骨骼稳定性的治疗效果。
回顾性分析了 57 例连续患者的资料，其中 30 例行单颌 Le Fort I 截骨术，27 例行双侧矢状劈开截骨术（BSSO），均未行额外手术。共获得 6 个阶段的侧位头颅侧位片（治疗前至术后 3 年）。
术后，87%的 Le Fort I 患者和 63%的 BSSO 患者出现正覆牙合，术后 6 个月时，这一比例分别为 90%和 74%。术后 3 年，Le Fort I 组 74%的患者和 BSSO 组 42%的患者出现正覆牙合。Le Fort I 组前颅面高度降低，BSSO 组增加，下颌平面角均减小。Le Fort I 组基本保持稳定，而 BSSO 组 80%的患者下颌平面角出现临床显著复发（≥2°）。
考虑到回顾性临床研究的局限性，可以得出以下结论。上颌或下颌手术治疗 II 类开牙合畸形时，大多数患者的前牙咬合可显著改善。但在治疗后，前后向和垂直向均会发生较大变化。虽然需要考虑个体形态，但 Le Fort I 手术的短期和长期稳定性似乎均优于 BSSO。
