Zhang Ke, Huang Lan, Yang Lin, Xu Li, Xue Chaoran, Xiang Zichao, Zhao Mengyuan, Li Song, Bai Yuxing, Bai Ding
a Lecturer, Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, China.
b Lecturer, Department of Orthodontics, School of Stomatology, Chongqing Medical University, Chongqing, China.
Angle Orthod. 2016 Jan;86(1):135-41. doi: 10.2319/101514.1. Epub 2015 Apr 29.
To identify the ideal ratios between the widths of the maxillary arch, mouth, and face, respectively, and to determine the range of acceptable esthetic variations based on these ideal ratios.
A photograph of a young female with a harmonious smile was selected and digitally altered to produce two sets of images. The first image showed an altered intercanine width, while the second one showed an altered oral fissure breadth. These alterations were independently rated by judges, including 23 orthodontists and 30 undergraduates. The Mann-Whitney U-test was used to compare the scores given by male and female judges and those given by professional and nonprofessional judges.
The following ideal transverse ratios were determined: intercanine width/oral fissure breadth, 0.638; oral fissure breadth/interparopia width: the distance between left and right paropia, 0.617; and intercanine width/face width at the level of the labial commissures, 0.300. A range of -10% to +10% was proposed as the thresholds of esthetic smile evaluations. It was shown that gender of the raters had no effect on the rating of photographs, nor were there any statistically significant differences between the professional and nonprofessional judges' ratings.
Balanced transverse relationships in the facial region are important for smile esthetics, and there is a wide range of esthetically acceptable variations in the transverse relationships between the maxillary arch, mouth, and face.
分别确定上颌牙弓宽度、口裂宽度与面部宽度之间的理想比例，并基于这些理想比例确定可接受的美学变异范围。
选择一张年轻女性具有和谐微笑的照片，并进行数字处理以生成两组图像。第一张图像显示改变后的尖牙间宽度，第二张图像显示改变后的口裂宽度。这些改变由包括23名正畸医生和30名本科生在内的评判员独立评分。采用曼-惠特尼U检验比较男性和女性评判员以及专业和非专业评判员给出的分数。
确定了以下理想的横向比例：尖牙间宽度/口裂宽度为0.638；口裂宽度/左右颧突间宽度（左右颧突之间的距离）为0.617；尖牙间宽度/口角水平处的面部宽度为0.300。建议将-10%至+10%的范围作为美学微笑评估的阈值。结果表明，评判员的性别对照片评分没有影响，专业和非专业评判员的评分之间也没有统计学上的显著差异。
面部区域的横向关系平衡对微笑美学很重要，上颌牙弓、口和面部之间的横向关系存在广泛的美学可接受变异范围。
