Department of Craniofacial Orthodontics, Chang Gung Memorial Hospital, Taipei, Taiwan.
Craniofacial Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
Sci Rep. 2019 Nov 29;9(1):17956. doi: 10.1038/s41598-019-54317-5.
The study aimed to evaluate the treatment outcome of bimaxillary surgery for class II asymmetry and find the influencing factors for residual asymmetry. Cone-beam computed tomographic images of 30 adults who had bimaxillary surgery were acquired, and midline and contour landmarks of soft tissue and teeth were identified to assess treatment changes and outcome of facial asymmetry. The postoperative positional asymmetry of each osteotomy segment was also measured. After surgery, the facial midline asymmetry of the mandible, chin, and lower incisors improved significantly (all p < 0.01). However, the residual chin deviation remained as high as 2.64 ± 1.80 mm, and the influencing factors were residual shift asymmetry of the mandible (p < 0.001), chin (p < 0.001), and ramus (p = 0.001). The facial contour asymmetry was not significantly improved after surgery, and the influencing factors were the initial contour asymmetry (p < 0.001), and the residual ramus roll (p < 0.001) or yaw (p < 0.01) asymmetry. The results showed that bimaxillary surgery significantly improved midline but not contour symmetry. The postoperative midline and contour asymmetry was mainly affected by the residual shift and rotational jaw asymmetry respectively.
本研究旨在评估双颌手术治疗 II 类不对称的治疗效果，并找出残留不对称的影响因素。对 30 例接受双颌手术的成年人进行锥形束 CT 扫描，确定软组织和牙齿的中线和轮廓标志，以评估面部不对称的治疗变化和结果。还测量了每个截骨段术后的位置不对称性。术后，下颌、颏和下切牙的面部中线不对称性显著改善（均 p<0.01）。然而，颏部的残留偏差仍高达 2.64±1.80mm，影响因素为下颌（p<0.001）、颏（p<0.001）和髁突（p=0.001）的残留移位不对称。术后面部轮廓不对称无明显改善，影响因素为初始轮廓不对称（p<0.001）和残留髁突滚转（p<0.001）或偏斜（p<0.01）不对称。结果表明，双颌手术显著改善了中线，但没有改善轮廓对称性。术后中线和轮廓不对称主要受残留的颌骨移位和旋转不对称影响。
