The bilateral sagittal split osteotomy is considered the standard surgery to correct facial asymmetries. More recently, unilateral sagittal split osteotomy (USSO) was used to treat such malocclusions. To assess facial symmetry following USSO in the treatment of class III laterognathia. Frontal facial photographs of four groups of patients were assessed: (1) pre-surgical group (n = 30) with skeletal asymmetry, (2) postsurgical group assessing patients of the first group 2 years after USSO, (3) control group (n = 30) of patients judged to have harmonious facial norms, and (4) mirrored group (n = 30) in which the control photographs were altered by duplicating the right half side of the face to replace the left half, thus creating perfectly symmetrical faces. All 120 photographs were distributed to 40 expert orthodontists to evaluate and score facial symmetry using the visual analog scale. Skin sensitivity and temporomandibular joint (TMJ) disorders were also assessed clinically pre and postsurgically. Statistically significant differences were observed between the pre-surgical group and each of the postsurgical and control groups (p < 0.001). The control and postsurgical groups received similar scores of symmetry (p = 0.774). The mirrored group received statistically significantly higher symmetry scores than either of the control or the postsurgical groups (p < 0.001). A reduction in TMJ disorders was noted after USSO and all patients reported normal skin sensation 2 years post-surgery. When indicated, USSO is a dependable and practical surgical approach to correct facial asymmetries associated with class III malocclusion.

中文翻译：

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单侧矢状切开截骨术：对下颌对称性Ⅲ类的治疗对下颌对称性的影响。

双侧矢状劈开截骨术被认为是纠正面部不对称的标准手术。最近，单侧矢状切开截骨术（USSO）被用于治疗此类错牙合畸形。评估USSO治疗III类红细胞增多症后的面部对称性。评估了四组患者的正面面部照片：（1）骨不对称的手术前组（n = 30），（2）USSO后2年的第一组患者的术后组，（3）对照组（n = 30）被判定具有和谐的面部规范的患者，以及（4）镜像组（n = 30），其中通过复制面部的右半边以替换左半边来更改对照照片，从而创建完美对称的面孔。将所有120张照片分发给40位专业的正畸医生，以使用视觉模拟量表对面部对称性进行评估和评分。皮肤敏感性和颞下颌关节（TMJ）疾病也进行了临床前和术后评估。术前组与术后组和对照组之间的差异均有统计学意义（p <0.001）。对照组和术后组的对称性评分相似（p = 0.774）。与对照组或术后组相比，镜像组的对称性评分在统计学上显着更高（p <0.001）。USSO后发现TMJ障碍有所减轻，所有患者术后2年均报告皮肤感觉正常。指示时，