Analysis of cephalometric indices which are consistent with subjective evaluation for facial asymmetry.

本研究的目的是探讨面部不对称的主观评价与头颅测量指标之间的关系。10名正畸医生主观评价100名受试者的正面照片，并将其分为三类，即第一类，对称视图；第二类，不需要处理的不对称；第三类，明显不对称，需要处理。通过对脑额片上的7项指标进行比较，确定各类别的特征。在第一类和第二类之间，没有发现任何指标的差异。5项指标显示第三类与其他类别之间存在差异。其中Me与垂直基准线的距离是主观评价面部不对称最相关的指标。当骨骼测量值与主观评价值之间存在差异时，应更多地考虑软组织结构对面部不对称的影响。接下来，我们试图确定颅面测量指标的阈值，通过正畸医生主观区分需要治疗面部不对称的患者（B组）和不需要治疗的患者（A组）在100名受试者的正面照片上。并对100例受试者的额叶脑电图进行5项指标的分析。对于每个正畸医生，通过判别分析确定阈值。随着判定需要治疗的受试者数量的增加，头测指标的阈值变小，判别准确率降低。在5个评价指标中，与Me相关的指标Me距离（平均4.28 mm）和上颌中线角（平均4.31度）的准确性最高。下颌下颌中线角和下颌下颌中线距离是评价面部不对称的最重要的主观指标，本研究确定的阈值对正畸治疗的规划和评价具有潜在的指导意义。少

The purpose of this study was to investigate the relationship between the subjective evaluation of facial asymmetry and cephalometric indices. Ten orthodontists subjectively evaluated the frontal photographs of 100 subjects and categorized them into three categories, ie, category I, symmetrical view ; category II, a little asymmetry not requiring treatment ; and category III, marked asymmetry requiring treatment. Seven indices on the frontal cephalographs were obtained and compared between the categories in order to define the characteristics of each category. No differences were found in any of the indices between categories I and II. Five indices showed differences between category III and the other categories. Among them, the distance of Me from the vertical reference line was the most relevant index for the subjective evaluation of facial asymmetry. When a discrepancy is found between skeletal measurements and a subjective evaluation, the influence of soft tissue structures should … More be considered in facial asymmetry.Next, we tried to determine the threshold of cephalometric indices, by which orthodontists subjectively differentiated patients requiring treatment for facial asymmetry (Group B) from those who did not (Group A) on the frontal photographs of 100 subjects. The frontal cephalographs of these 100 subjects were also analyzed for 5 indices. For each orthodontist, the threshold was determined by means of the discriminant analysis. As the number of subjects, who were judged to require treatment, increased, the threshold of cephalometric indices became small and the discriminant accuracy was reduced. Among the 5 indices evaluated, the distance of Me (mean : 4.28 mm) or maxillo-mandibular midline angle (mean : 4.31 degree), which were the indices related to the Me, showed the highest accuracy in all observers. The distance of the Me and the maxillo-mandibular midline angle appeared to be the most relevant indices for subjective evaluation of facial asymmetry and the threshold determined in the present study has the potential to contribute to the planning and evaluation of orthodontic treatments. Less