手术优先的BSSRO-术后正畸治疗下颌前突的稳定性研究

Stability of Operation-first BSSRO Combined Postoperative Orthodontic Treatment for Mandibular Prognathism

目的通过头影测量探讨手术优先的双侧下颌升支矢装劈开术(Bilateral sagittal split ramus osteotomy,BSSRO)-术后正畸治疗下颌前突(Mandibular prognathism,MP)的稳定性。方法从2012年1月至2014年10月,18位MP伴/不伴面部不对称患者进行手术优先的BSSRO-术后正畸治疗。术前(T0)、术后5天(T1)及术后1年及以上(T2)拍摄头颅侧位X线片。测量骨骼标志点的移动距离及相关角度的变化。结果在水平向,B点在T1较T0平均后退7.5 mm,在T2较T1平均前移2.1 mm(28.0%);Pog点在T1较T0平均后退6.6 mm,在T2较T1平均前移2.9 mm(43.9%)。在垂直向上,B点(1.3 mm)和Pog点(1.0 mm)在T1平均向下移;B点和Pog点在T2都出现了上移,分别为0.1 mm(7.7%)和0.3 mm(30.0%)。Ramus angle在T1较T0平均增加4.3°,在T2较T1平均减小1.1°(25.6%)。在水平向和垂直向,B点和Pog点的后退距离(T1-T0)与术后长期改变的距离(T2-T1)无显著相关性(P>0.05)。在水平向,Ramus angle、Go和Condylion的改变(T1-T0)与Pog点的改变(T2-T1)无显著相关性(P>0.05)。结论手术优先的BSSRO-术后快速正畸治疗MP在水平向、垂直向都存在一定的复发率;无论在水平向还是垂直向,B点和Pog点的复发程度与其后退幅度无显著线性相关性。

Objective To explore the stability of operation-first sagittal split ramus osteotomy（SSRO）-postoperative orthodontics therapy for the correction of mandibular prognathism（MP） by cephalometric radiographs. Methods Eighteen patients diagnosed with MP with and without asymmetry were treated. BSSRO-postoperative rapid orthodontics therapy was performed without preoperative orthodontics therapy and lateral cephalometric radiographs were taken before operation（T0）,five days after operation（T1） and one year after operation（T2）. The landmarks were measured by the software. Results The mean surgical setback was 7.5 mm at B point and 6.6 mm at pogonion. The mean long-term horizontal relapse was 2.1 mm（28.0%） at B point and 2.9 mm（43.9%） at pogonion. The mean vertical surgical changes showed downward displacement of B point（1.3 mm） and pogonion（1.0 mm）. The mean long-term vertical relapse was 0.1 mm at B point and 0.3 mm at pogonion.The mean increase was 4.3 ° at ramus angle and the long-term relapse was 1.1 °（25.6%）. The magnitude of the surgical movement of B point and pogonion（T1-T0） didn ＇t correlate with long-term changed distance（T2-T1） horizontally and vertically（P0.05）. The magnitude of the surgical movement of Go, Condylion point and ramus angle（T1-T0） didn ＇t correlate with long-term changed distance of Pog point（T2-T1） horizontally（P 0.05）. Conclusion The skeletal relapse do exist in the BSSRO-postoperative rapid orthodontics therapy for MP and there is no linear correlation between the surgical movement of B point, pogonion and skeletal relapse.