三维测量技术在骨性Ⅲ类错颌双颌术后复发研究中的应用

Application of three-dimensional measurement technology in the study of relapse after bimaxillary surgery in skeletal ClassⅢmalocclusion patients

目的探讨三维测量方法应用于骨性Ⅲ类错颌畸形患者正颌术后颌骨稳定性研究的可行性,分析术后颌骨的复发情况及其影响因素。方法以2019年7至12月于南京大学医学院附属口腔医院口腔颌面外科行双颌手术的骨性Ⅲ类错颌畸形患者为研究对象,患者均行上颌Le Fort Ⅰ型截骨术+双侧下颌矢状劈开术。收集患者术前1周(T0)、术后3 d(T1)、术后6~12个月(T2)螺旋CT数据,使用3D Slicer建模并导入Geomagic Qualify拟合配准、测量上、下颌骨各标志点三维移动距离。对T1、T2期各标志点坐标值行配对t检验或Wilcoxon符号秩和检验,并对有明显复发的标志点之间行Pearson相关性分析,P < 0.05为差异有统计学意义。结果共纳入15例患者,其中男5例,女10例,年龄18~25岁,平均21.3岁。T1与T2期各标志点水平向坐标值比较,仅在右下颌角点差异有统计学意义,T1期为(-50.47±4.44) mm,T2期为(-50.06±4.66) mm(t=2.948,P=0.011)。T1与T2期各标志点前后向坐标值比较,上颌骨上牙槽座点、左、右梨状孔点、左、右骨折线中点差异有统计学意义(P<0.05),复发率分别为37.7 %(1.36/3.61)、35.7%(1.15/3.22)、25.4%(0.84/3.31)、26.9%(0.84/3.12)、14.0%(0.41/2.92);下颌骨下牙槽座点、颏前点、颏顶点、颏下点、左、右下颌角点差异有统计学意义(P<0.01),复发率分别为36.9%(1.75/4.74)、53.9%(2.45/4.55)、55.5%(2.72/4.90)、61.7%(2.90/4.70)、85.3%(2.20/2.58)、93.4%(2.40/2.57);复发距离与移动距离均显著相关(r值为0.572~0.736,P < 0.05)。T1、T2期垂直向各标志点坐标值比较,上颌骨垂直向差异无统计学意义(P>0.05);下颌骨下牙槽座点、颏前点、颏顶点、颏下点差异有统计学意义(P<0.01),T2期较T1期发生明显的逆时针旋转。结论三维测量方法可准确反映骨性Ⅲ类错颌畸形患者双颌术后颌骨的三维变化,术后上、下颌骨在水平向均无明显复发,在前后向均存在复发,与手术距离显著相关,在垂直向仅下颌骨存在旋转移位。

Objective To evaluate the feasibility of three-dimensional measurement in the study of jaw stability in patients with skeletal ClassⅢmalocclusion after orthognathic surgery,and to analysis the jaw relapse of risk factors.Methods Patients with skeletal ClassⅢmalocclusion who underwent bimaxillary surgery in Department of Oral and Maxillofacial Surgery,Nanjing Stomatological Hospital,from July 2019 to December 2019 were included.CT data at 1 week preoperative(T0),3 days after surgery(T1),and 6-12 months after surgery(T2)were collected respectively.The 3D model was constructed by 3D Slicer,and the movement of maxilla and mandible after surgery was measured by Geomagic Qualify.The paired student t-test,Wilcoxon rank sum test and Pearson correlation was performed in this study.P<0.05 was considered statistically significant.Results A total of 15 patients were included,including 5 males and 10 females.The age is from 18 to 25 year old.The average age is 21.3.In horizontal direction,the RGo coordinate has significant difference between T1[(-50.47±4.44)mm]and T2[(-50.06±4.66)mm](t=2.948,P=0.011),while all other landmarks have no significantly statistic difference.In the anteroposterior direction,there were significant differences for all maxillary landmarks between T1 with T2(P<0.05).The relapse rates at point of A,Rp,Lp,RMF and LMF were 37.7%(1.36/3.61),35.7%(1.15/3.22),25.4%(0.84/3.31),26.9%(0.84/3.12),14.0%(0.41/2.92),respectively.There were significant differences in all mandibular landmarks between T1 with T2(P<0.01).The relapse rates at point of B,Pog,Gn,Me,RGo and LGo were respectively 36.9%(1.75/4.74),53.9%(2.45/4.55),55.5%(2.72/4.90),61.7%(2.90/4.70),85.3%(2.20/2.58),93.4%(2.40/2.57).The distance of skeletal relapse movement was significantly correlated with the surgery-induced distance(r:0.572-0.736,P<0.05).In the vertical direction,there was no significant difference of maxillary landmarks between T1 with T2(P>0.05).For B,Pog,Gn and Me points,there were statistically significant differences(P<0.01).From T1 to T2,the mandible has tendency of counter-clockwise rotation.Conclusions The three-dimensional measurement can accurately reflect the three-dimensional changes of jaw in patients with skeletal ClassⅢmalocclusion after bimaxillary surgery.No significantly statistic relapse was in horizontal direction,while obvious relapse was occurred in anteroposterior directions.The counter-clockwise rotation of mandible was shown in vertical direction.