Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, People's Republic of China.
Laboratory Center of Stomatology, College of Stomatology, Xi'an Jiaotong University, Xi'an, People's Republic of China.
BMC Oral Health. 2023 Apr 14;23(1):214. doi: 10.1186/s12903-023-02893-4.
The purpose of this study was to compare the perception of upper dental midline deviation on the attractiveness of a smile among raters from different ethnicities, professions, genders, and ages and measure to what extent the presence or absence of the associated smiling structures influence the raters' evaluations.
A male subject (26 years of age) with adequate smile characteristics was selected by 3 experienced orthodontists, and 561 raters from 2 different ethnic groups (281 Chinese raters and 280 Black raters) rated the subject's smile after the subject's upper dental midline was digitally altered from 0 to 5 mm using a 5-point Likert scale on 12 smile photographs divided into two groups: group 1, in the presence of smile related structures, two-thirds of the nose, lips, and chin (NLC), and group 2, in the absence of smile related structures, the lips only (L).
There were statistically significant differences (p < 0.05) between the two ethnicities, in 2 mm and 4 mm in-group NLC and 5 mm in-group L, as well as the raters' profession to each midline shift of both groups (NLC) and (L) for both ethnicities except for 0 mm. Regarding the role of associated smile structures, the smile photos were observed in the presence of smile-associated structures, and in its absence (NLC × L), statistically significant differences (p < 0.05) were found when the deviation was 5 mm among the Chinese raters; in 1 mm, and 4 mm among the Black raters. Among different genders, statistical differences were only reported (p < 0.05) for Chinese raters for 5 mm in NLC, while statistical differences were observed for 2 mm and 3 mm in NLC for Black raters. For age categories, differences were observed (p < 0.05) for 4 mm, 5 mm in NLC and 4 mm, and 5 mm in L for Chinese raters, while 5 mm in NLC and 1 mm in L for Black raters.
Perception of the upper dental midline deviations was influenced by the factors of ethnicity, profession, presence or absence of smile-associated structures, as well as the gender and age of the raters.
本研究的目的是比较不同种族、职业、性别和年龄的评价者对上颌牙齿中线偏斜对微笑吸引力的感知，并衡量相关微笑结构的存在与否对评价者评估的影响程度。
由 3 名经验丰富的正畸医生选择一名具有适当微笑特征的男性受试者（26 岁），然后由来自两个不同种族（281 名中国评价者和 280 名黑人评价者）的 561 名评价者对受试者的微笑进行评估，评估时使用 5 分制的李克特量表对受试者的上颌牙齿中线从 0 到 5 毫米进行数字化改变，共拍摄了 12 张微笑照片，分为两组：组 1，有微笑相关结构，三分之二的鼻子、嘴唇和下巴（NLC）；组 2，无微笑相关结构，只有嘴唇（L）。
两个种族之间在 2mm 和 4mm 内组 NLC 和 5mm 内组 L 以及评价者的职业对两组（NLC）和（L）的每条中线移位都有统计学差异（p<0.05），除了 0mm 外，两个种族都没有。关于相关微笑结构的作用，在存在微笑相关结构和不存在（NLC×L）的情况下观察到微笑照片，在 5mm 时，中国评价者的偏差有统计学差异（p<0.05）；在 1mm 和 4mm 时，黑人评价者的偏差有统计学差异。在不同性别中，仅报告了中国评价者的统计学差异（p<0.05），在 NLC 中为 5mm，而在 NLC 中为 2mm 和 3mm，黑人评价者的统计学差异明显。对于年龄类别，中国评价者的 4mm、5mm 的 NLC 和 4mm、5mm 的 L 存在差异（p<0.05），而黑人评价者的 5mm 的 NLC 和 1mm 的 L 存在差异。
上齿中线偏差的感知受到种族、职业、有无微笑相关结构以及评价者的性别和年龄等因素的影响。
