骨性Ⅲ类错[牙合]畸形患者正颌术后颏部软组织和骨组织形态变化及其影响因素分析

Analysis on morphological changes of soft and bone tissues in chin of patients with skeletal classⅢmalocclusion after orthognathic operation and its influence factors

目的:探讨三维方向上骨性Ⅲ类错[牙合]畸形患者正颌术后颏部软组织和骨组织形态变化,并分析其影响因素。方法:收集于本院行双颌正颌手术的成人患者19例,其中男性患者9例,女性患者10例。所有患者于术前1周(T0)和术后12个月(T1)进行全头颅计算机断层扫描(CT)获取面部数据,采用ProPlan CMF 3.0软件进行术前及术后面部软组织和骨组织的三维重建和配准。测量并计算颏部软组织厚度和解剖标记点于水平、矢状和垂直向上移动量的相关性及比值。结果:正颌术后下颌后退量以下唇红唇及颏唇沟区最大,沿此区域向周边扩散软组织后退量逐渐递减。颏下区后退量较小,在颏下点处颏部有前出趋势。与T0时比较,T1时下唇度突点(LL)软组织厚度增加(P<0.05)。线性回归分析,水平向(X)上,随着骨组织向左移动,颏部软组织解剖标记点LL(B=0.795,R^(2)=0.832)、颏唇沟点(Si)(B=0.876,R^(2)=0.987)、软组织颏前点(Pos)(B=0.890,R^(2)=0.971)和软组织颏下点(Mes)(B=0.942,R^(2)=0.978)均呈负向改变,向左移动,软组织和骨组织移动方向一致;矢状向(Y)上,随着骨组织向后移动,颏部软组织解剖标记点LL(B=0.882,R^(2)=0.934)、Si(B=0.946,R^(2)=0.847)、Pos(B=0.839,R^(2)=0.909)和Mes(B=0.666,R^(2)=0.455)均向后移动,软组织和骨组织组织移动方向一致;垂直向(Z)上,随着骨组织的上移,颏部软组织解剖标记点LL(B=0.932,R^(2)=0.686)、Si(B=0.834,R^(2)=0.469)和Mes(B=0.925,R^(2)=0.709)均向下移动;Pos(B=0.487,R^(2)=0.444)向上移动。在水平、矢状和垂直向上各颏部解剖标记点软组织移动量(ΔSM)和骨组织移动量(ΔBM)相关性较强(0.6<r<1.0,P<0.01)。结论:骨性Ⅲ类错[牙合]畸形患者正颌术后水平、矢状和垂直向上颏部软组织变化均受骨组织移动的影响,且呈正相关关系,水平向和矢状向相关性较强,垂直向相关性较弱。

objective:To discuss the morphological changes and related factors of soft and bone tissues in chin in the skeletal classⅢmalocclusion patients at three dimensions after orthognathic operation.Methods:A total of 19 adult patients underwent orthognathic operation were collected,including 9 males and 10 females.All the patients received craniofacial computed tomography(CT)scans one week before operation(T0)and 12 months after(T1)operation to obtain the facial data of the soft and bone tissues,with a three-dimensional reconstruction and registration by using ProPlan CMF 3.0 software.The measurements and calculations were made on the thickness of chin soft tissue,the horizontal,sagittal,and vertical changes in anatomical landmarks,and the correlation and ratios between them.Results:The most significant retrusion of soft tissue after operation was in the lower lip vermilion and the mentolabial fold area.The posterior displacement of soft tissue was gradually decreased,spreading from this area to the periphery.The posterior change in the submental area was relatively minor,with an anterior trend at the submental point.Compared with T0 time point,the soft tissue thickness at the lower lip(LL)at T1 time point was increased(P<0.05).The linear regression analysis results showed that at the horizonta(l X),as the bone tissue changed to the left,the anatomical landmarks of soft tissue in chin LL(B=0.795,R^(2)=0.832),mentolabial sulcus(Si)(B=0.876,R^(2)=0.987),soft tissue pogonion(Pos)(B=0.890,R^(2)=0.971),and menton of soft tissue(Mes)(B=0.942,R^(2)=0.978)showed negative changes,all moved to the left;the movement directions of soft and bone tissues were consistent.At the sagittal(Y)direction,as the bone tissue moved backward,the LL(B=0.882,R^(2)=0.934),Si(B=0.946,R^(2)=0.847),Pos(B=0.839,R^(2)=0.909)and Mes(B=0.666,R^(2)=0.455)all moved backward,and the movement directions of soft and bone tissues were consistent.At the vertical(Z)direction,as the bone tissue moved upwards,the LL(B=0.932,R^(2)=0.686),Si(B=0.834,R^(2)=0.469),and Mes(B=0.925,R^(2)=0.709)moved downwards,while the Pos(B=0.487,R^(2)=0.444)moved upwards.In horizontal,sagittal,and vertical directions,the correlation between soft-tissue movement(ΔSM)and bone-tissue movement(ΔBM)of chin anatomical landmarks was generally strong(0.6<r<1.0,P<0.01).Conclusion:The changes of soft and hard tissues in the chin of skeletal classⅢmalocclusion patients at horizontal,sagittal,and vertical directions after orthognathic operation are influenced by bone tissue movements,showing the positive correlation.The correlations at the horizontal and sagittal directions are stronger,and the correlation at the vertical direction is weaker.