Richards Michael R, Fields Henry W, Beck F Michael, Firestone Allen R, Walther Dirk B, Rosenstiel Stephen, Sacksteder James M
Resident, Division of Orthodontics, College of Dentistry, Ohio State University, Columbus, Ohio.
Professor and chair, Division of Orthodontics, College of Dentistry, Ohio State University, Columbus, Ohio.
Am J Orthod Dentofacial Orthop. 2015 Apr;147(4):472-82. doi: 10.1016/j.ajodo.2014.12.016.
There is disagreement in the literature concerning the importance of the mouth in overall facial attractiveness. Eye tracking provides an objective method to evaluate what people see. The objective of this study was to determine whether dental and facial attractiveness alters viewers' visual attention in terms of which area of the face (eyes, nose, mouth, chin, ears, or other) is viewed first, viewed the greatest number of times, and viewed for the greatest total time (duration) using eye tracking.
Seventy-six viewers underwent 1 eye tracking session. Of these, 53 were white (49% female, 51% male). Their ages ranged from 18 to 29 years, with a mean of 19.8 years, and none were dental professionals. After being positioned and calibrated, they were shown 24 unique female composite images, each image shown twice for reliability. These images reflected a repaired unilateral cleft lip or 3 grades of dental attractiveness similar to those of grades 1 (near ideal), 7 (borderline treatment need), and 10 (definite treatment need) as assessed in the aesthetic component of the Index of Orthodontic Treatment Need (AC-IOTN). The images were then embedded in faces of 3 levels of attractiveness: attractive, average, and unattractive. During viewing, data were collected for the first location, frequency, and duration of each viewer's gaze.
Observer reliability ranged from 0.58 to 0.92 (intraclass correlation coefficients) but was less than 0.07 (interrater) for the chin, which was eliminated from the study. Likewise, reliability for the area of first fixation was kappa less than 0.10 for both intrarater and interrater reliabilities; the area of first fixation was also removed from the data analysis. Repeated-measures analysis of variance showed a significant effect (P <0.001) for level of attractiveness by malocclusion by area of the face. For both number of fixations and duration of fixations, the eyes overwhelmingly were most salient, with the mouth receiving the second most visual attention. At times, the mouth and the eyes were statistically indistinguishable in viewers' gazes of fixation and duration. As the dental attractiveness decreased, the visual attention increased on the mouth, approaching that of the eyes. AC-IOTN grade 10 gained the most attention, followed by both AC-IOTN grade 7 and the cleft. AC-IOTN grade 1 received the least amount of visual attention. Also, lower dental attractiveness (AC-IOTN 7 and AC-IOTN 10) received more visual attention as facial attractiveness increased.
Eye tracking indicates that dental attractiveness can alter the level of visual attention depending on the female models' facial attractiveness when viewed by laypersons.
关于口腔在整体面部吸引力中的重要性，文献中存在分歧。眼动追踪提供了一种评估人们所看内容的客观方法。本研究的目的是使用眼动追踪来确定牙齿和面部吸引力是否会改变观看者的视觉注意力，具体涉及面部的哪个区域（眼睛、鼻子、嘴巴、下巴、耳朵或其他）首先被观看、被观看的次数最多以及被观看的总时长最长。
76名观看者进行了一次眼动追踪实验。其中，53名是白人（49%为女性，51%为男性）。他们的年龄在18至29岁之间，平均年龄为19.8岁，且均非牙科专业人员。在定位和校准后，向他们展示了24张独特的女性合成图像，每张图像展示两次以确保可靠性。这些图像反映了单侧唇裂修复情况或类似于正畸治疗需求指数美学部分（AC-IOTN）评估的1级（接近理想）、7级（临界治疗需求）和10级（明确治疗需求）的3个牙齿吸引力等级。然后将这些图像嵌入到3种吸引力水平的面部中：有吸引力、普通和无吸引力。在观看过程中，收集了每位观看者注视的首次位置、频率和时长的数据。
观察者信度范围为0.58至0.92（组内相关系数），但下巴的观察者间信度小于0.07，因此将其从研究中排除。同样，首次注视区域的信度在观察者内和观察者间均小于0.10（kappa值）；首次注视区域也从数据分析中去除。重复测量方差分析显示，面部区域、错颌畸形和吸引力水平之间存在显著影响（P<0.001）。对于注视次数和注视时长，眼睛在绝大多数情况下最为显著，嘴巴获得的视觉注意力次之。有时，在观看者的注视次数和时长方面，嘴巴和眼睛在统计学上没有差异。随着牙齿吸引力降低，嘴巴上的视觉注意力增加，接近眼睛的水平。AC-IOTN 10级获得的关注最多，其次是AC-IOTN 7级和唇裂。AC-IOTN 1级获得的视觉注意力最少。此外，随着面部吸引力增加，较低的牙齿吸引力（AC-IOTN 7和AC-IOTN 10）获得更多的视觉注意力。
眼动追踪表明，外行人观看时，牙齿吸引力会根据女性模特的面部吸引力改变视觉注意力水平。
