School of Odonto Stomatology, Hanoi Medical University, Hanoi 100000, Vietnam.
Department of Anatomy, University of Medicine Pham Ngoc Thach, Ho Chi Minh City 700000, Vietnam.
Int J Environ Res Public Health. 2020 Mar 3;17(5):1638. doi: 10.3390/ijerph17051638.
: It is important to meet the aesthetic expectation regarding the smile concept of both dentists and non-professionals after treatment is complete. Therefore, the study aims to evaluate the effects of altered displays in incisors, gingival margin, and other smile-related-factors on dentists' vs. non-professionals' aesthetics perceptions. : We altered the features of 42 digital smile photographs to generate the changed displays in incisors, gingival margin, and other smile-related-factors. Then, these altered photographs were presented to 51 dentists and 51 non-professionals, and each picture was rated by each participant with a visual analog scale ranging from 0 (very ugly) to 100 (very beautiful). : We found that the alterations in incisors, gingival margin, and other factors affected studied groups' aesthetic perception of smile. The ugly smile threshold rated by both groups for crown length of maxillary central incisors was 2.0 mm. This threshold was 2.5mm for dentists, with moving the gingival margin of maxillary lateral incisors to the incisal ridge. The ugly thresholds for other smile-related-factors were different between studied groups; for example, the ugly thresholds for gingival exposure levels were 3 and 4mm for dentists and non-professionals, respectively. Thus, our data indicate that altered displays in incisors, gingival margin, and other smile-related-factors affected perceptions of both studied groups on smile aesthetics, but dentists tended to feel more refined than non-professionals. Dentists and non-professionals had significantly different aesthetic perceptions of the alteration of the gingival exposure level. : Both dentists and non-professionals' perceptions should be fully considered during orthodontic and prosthodontic treatment to achieve optimum aesthetic results.
：治疗完成后，满足牙医和非专业人士对微笑概念的审美期望非常重要。因此，本研究旨在评估改变切牙、牙龈边缘和其他与微笑相关因素的显示对牙医和非专业人士美学感知的影响。
：我们改变了 42 张数字化微笑照片的特征，以生成切牙、牙龈边缘和其他与微笑相关因素的变化显示。然后，这些改变后的照片呈现给 51 名牙医和 51 名非专业人士，每位参与者使用视觉模拟量表对每张照片进行评分，范围从 0（非常丑）到 100（非常美）。
：我们发现，切牙、牙龈边缘和其他因素的改变影响了研究组对微笑的审美感知。两组对上颌中切牙冠长的丑陋微笑阈值评定为 2.0 毫米。对于牙医来说，这个阈值是 2.5 毫米，即将上颌侧切牙的牙龈边缘移到切缘。其他与微笑相关因素的丑陋阈值在两组之间有所不同；例如，对于牙医和非专业人士来说，牙龈暴露水平的丑陋阈值分别为 3 毫米和 4 毫米。因此，我们的数据表明，切牙、牙龈边缘和其他与微笑相关因素的改变显示会影响两组对微笑美学的感知，但牙医比非专业人士更倾向于感到更精细。牙医和非专业人士对牙龈暴露水平改变的美学感知有显著差异。
：在正畸和修复治疗中，应充分考虑牙医和非专业人士的意见，以达到最佳的美学效果。
