非对称性经缝牵引成骨术在青少年单侧唇腭裂严重面中部骨骼发育不全中的应用

目的探讨非对称性经缝牵引成骨术在青少年单侧唇腭裂患儿严重面中部骨骼发育不全中的治疗效果。方法回顾性分析2011年1月至2020年12月中国医学科学院整形外科医院收治的单侧唇腭裂术后严重面中部骨骼发育不全的青少年患儿资料,均行非对称性经缝牵引治疗,采用颅骨外固定支架联合镍钛记忆合金弹簧的尖牙支柱骨承力牵引方式,对两侧上颌骨施加不同大小的牵引力,并通过适度的牵引矫枉过正处理、及时的正畸治疗和适时的面弓牵引维持策略预防术后复发。通过对牵引前后的上牙槽座点(A)、梨状孔外侧缘点(LPA)、鼻颌缝最下点(INM)以及翼上颌缝点(PTM)到过蝶鞍点冠状面(CR平面)距离进行测量,分析对比面中部骨骼裂隙侧与非裂隙侧的变化,计算INM、LPA及PTM点的非对称率。结果研究共纳入38例患儿,其中男34例,女4例,年龄8~15岁。所有患儿均顺利完成牵引治疗,术后面形及咬合关系得到显著改善。术后随访1~3年,结果显示牵引结束时因矫枉过正所致面中部凸出及咬合超覆盖会在6~12个月后恢复协调,3例术后未接受面弓牵引维持的患儿于随访3年后出现不同程度的上颌复发。对其中25例患儿牵引前后头颅CT影像进行分析,结果显示A点前移量为(12.67±4.62)mm(6.21~23.28 mm)。牵引前裂隙侧INM、LPA及PTM点到CR平面的距离均小于非裂隙侧,差异具有统计学意义(P<0.05),而在牵引结束后INM和PTM点的两侧距离差异无统计学意义(P>0.05),LPA点的两侧距离差值虽然有缩小,但裂隙侧仍显著小于非裂隙侧,差异具有统计学意义(P<0.05)。与牵引前相比,牵引结束后INM、LPA及PTM点的非对称率均有显著的降低,差异具有统计学意义(P<0.05)。结论非对称性经缝牵引成骨术为临床上青少年单侧唇腭裂患儿严重面中部骨骼发育不全的早期矫治提供了一种有效方法,并能很好地恢复面中部对称性。

Application of asymmetric trans-sutural distraction osteogenesis for severe midfacial hypoplasia in growing patients with unilateral cleft lip and palate

Objective To investigate the effects of asymmetric trans-sutural distraction osteogenesis for severe midfacial hypoplasia in growing patients with unilateral cleft lip and palate.Methods All the growing patients with unilateral cleft lip and palate combining severe midfacial hypoplasia treated with asymmetric trans-sutural distraction osteogenesis from January 2011 to December 2020 in the Plastic Surgery Hospital,Chinese Academy of Medical Sciences were analyzed retrospectively.The distraction system consisted of the bone-borne traction hooks,nickel-titanium shape memory alloy spring and rigid external distractor.Asymmtric distraction could be achieved by exerting different traction force to bilateral maxilla.The technique for relapse prevention included moderate overcorrection,prompt orthodontic treatment and face mask therapy.The changes of midfacial symmetry between the cleft and non-cleft side were analyzed by comparing the distance of subspinale A-point(A),intersection of lateral border of piriform aperture and plane parallel to midsagittal reference plane(LPA),most inferior point on nasomaxillary suture(INM)and most inferior point on profile of pterygomaxillary suture(PTM)to coronal reference plane between preoperative and postoperative,and the asymmetric ratio of LPA,INM and PTM were calculated.Results A total of 38 patients,(34 males and 4 females,aged from 8-15 years)were included.All of the patients completed the distraction and achieved a satisfied improvement in the midface convexity and overjet.The postoperative 1-3 years follow-up showed the midface protrusion and occlusal overcoverage after distraction caused by overcorrection tended to become harmonious in the following 6 to 12 months,and 3 patients with no face mask therapy done had relapse on maxilla in various degrees after 3 years follow-up.The measurement findings of 25 patients showed the average advancement of A point was(12.67±4.62)mm(range,6.21-23.28 mm).The distances of INM,LPA and PTM to CR plane on the cleft side were significantly less than that on the non-cleft side before the distraction(P<0.05).However,after the distraction,these distance differences of INM and PTM between the cleft and non-cleft side were eliminated(P>0.05).The distance difference of bilateral LPA was reduced,but still significant less on the cleft side(P<0.05).Compared before and after distraction,the asymmetric rate of INM,LPA and PTM was significantly decreased(P<0.05).Conclusions Asymmetric trans-sutural distraction osteogenesis offers an effective method for the early treatment of severe midfacial hypoplasia in growing patients with unilateral cleft lip and palate,and restores the midfacial symmetry.