Smile aesthetics

The aim of this article is to outline some of the factors practitioners should take into consideration when planning optimal smile aesthetics. The components of the smile that will be discussed include the smile arc, incisor/gingival display, smile width, gingival aesthetics, tooth proportionality/symmetry, contacts/connectors/embrasures and the dental midlines. CLINICAL RELEVANCE: A systematic evaluation of the components of the smile when planning treatment will help to improve smile aesthetics and produce greater patient and dentist satisfaction.     

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??The gingival aesthetics is an important part of the smile aesthetics??as well as a great factor influencing the beauty of the lower 1/3 face. Such problems as the gingivitis??periodontitis??gingival hypertrophy and lack of gingival papilla will change the color??morphology??texture and quantity of gingiva. They also hurt the harmonious relationship between gingiva and the tissue around it. Consequently??those problems exert negative impacts on the gingival aesthetics and damage the beauty of smile. As for the treatment plan??different problems and individuals require personalized treatment plans. In this paper??the authors will make an introduction to the common problems affecting the gingival aesthetics and their treatment principles.     

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提要：上颌前牙区美学修复是口腔医学的重要组成部分。多数学者一直致力于牙体排列、大小、颜色等方面的研究,而对于牙龈美学的研究相对较少。牙龈美学作为微笑美学不可或缺的部分,也越来越受到医生和患者的重视。如何构建更为协调、美观的微笑,这使得学者们不得不共同关注牙齿、牙龈、口唇三者之间的美学参数。本文就上颌前牙区牙龈美学相关参数做一综述。     

Morphological features of smile attractiveness and related factors influence perception and gingival aesthetic parameters

IntroductionIn addition to understanding the basic standards of a smile and patient's opinion, dentists should take into account smile aesthetics, an essential factor for optimal outcomes. This study aimed to evaluate the factors that affect the perception of an aesthetic smile and determine its morphological characteristics and measure the gingival aesthetic parameters.MethodsIn all, 200 Vietnamese aged 18-35 years were recruited to have their spontaneous smiles captured. These smile images were assessed by 50 laypersons and 50 dentists using a visual analogue scale measurement. The images were analysed to evaluate perceptions of evaluators, determine smile attractiveness, and measure gingival aesthetics.ResultsThe difference in the judgements of laypersons and dentists, males and females, and laypersons aged 18-25 and 26-35 years were nonsignificant. High or average anterior smile line, parallel smile arc, upward upper lip curvature, second premolars as the posterior-most teeth displayed, smile index of 5.23-5.63, and dynamic smile symmetry of 1 were scored highly on smile attractiveness. The following maxillary gingival aesthetic parameters were preferred: gingival zenith (GZ) of the canine 0.72-0.75 mm apical to the GZ of the central incisor; GZ of the lateral incisor 0.66 mm coronal to the gingival line; gingival line angle of ～87°; for the central incisor, lateral incisor, and canines, distance from the GZ to the long axis of 1, 0.4, and 0 mm, respectively; interdental papilla height of 4.25, 3.60, and 3.85 mm, respectively; ratio of the distance from the GZ and the interdental papilla tip to the incisal edge of ～1.74-1.77 mm.ConclusionsFactors including profession, gender, and age of evaluators had almost no impact on their perception of aesthetics. Smile attractiveness characteristics and gingival aesthetic parameters have clinical applicability for patient care.     

The unique contribution of elements of smile aesthetics to psychosocial well‐being

Pleasant smile aesthetics is an important contributory factor to psychosocial well‐being. The aim of this study was to determine the psychosocial influence of smile aesthetics. The study was cross‐sectional on a convenient sample that included patients, pupils, students and faculty staff. A total of 155 subjects (36% male) aged 12–39 (mean age 21, interquartile range 19–23) were included. Occlusal characteristics were recorded by the Index of Complexity, Outcome and Need, and smiling frontal view photographs were obtained. Fourteen variables were measured using photogrammetric analysis: smile width, visibility of buccal corridors, maximum teeth exposure, total gingival display, lip thickness, degree of occlusal cant and deviation from golden proportion of the teeth in maxillary intercanine sector. Psychometric instruments included the Psychosocial Impact of Dental Aesthetics Questionnaire and the Rosenberg Self‐Esteem Scale. Statistical analysis comprised multiple linear regressions. Malocclusion severity is the most important predictor of psychosocial influence of smile aesthetics and self‐esteem, the unique contribution of which accounts for a total of 4–27% of variability. Female gender is associated with higher psychological influence of dental aesthetics while male gender and older age with self‐esteem. Malocclusions have higher psychosocial impact than parameters of mini‐ and micro‐aesthetics of smile related to visibility of buccal corridors, amount of teeth exposure, gingival display, lip thickness, presence of occlusal cant and deviation from golden proportion of the teeth. It appears that people are not as focused on details of their smile as they are on distinctive malposition of teeth.     

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??Aesthetics has got increasingly attention in the practice of today′ s dentistry. The smile is one of the most important facial expressions. A number of characteristic features were described to formulate a standard smile??including smile type??gingival contour??buccal corridor??etc. These parameters vary from study to study and have changed a lot in the recent decades. The present review aims to address the factors associated in the smile aesthetics.     

Perceptions of Jordanian laypersons and dental professionals to altered smile aesthetics

The purposes of this study were to rate the attractiveness of different smile variables, to compare the perception of Jordanian laypeople, general practitioners, and orthodontists to altered smile aesthetics, and to identify the threshold where different variables begin to impair smile aesthetics. A smiling photograph of a female dental student was selected and digitally manipulated to create changes in buccal corridor space (BCS), the amount of gingival display, and the midline diastema. These altered images were rated by three groups of Jordanians: 200 laypeople (100 females and 100 males), 200 general practitioners (100 females and 100 males), and 160 orthodontists (40 females and 120 males). Smile aesthetics scores were calculated and comparisons between groups were performed using the univariate general linear model. The results showed that profession and gender affected BCS and midline diastema attractiveness ratings (P<0.001). Wide BCSs, a gingival display of more than 2 mm, and the presence of a midline diastema of any size were rated as unattractive by all groups.     

Effect of extraction of first four premolars on smile aesthetics

The objective of the present study was to assess smile aesthetics after orthodontic treatment in subjects with and without the extraction of four first premolars. Post-treatment coloured frontal photographs (4 × 6 inches) of 60 Pakistani subjects, 21 males and 39 females, aged between 15 and 30 years were assessed by one examiner. For 50 per cent (n = 30) of the patients, treatment included the extraction of four first premolars, whereas the other half were treated without extractions. Smile aesthetics were evaluated by a panel of 10 laypersons, five males and five females, aged between 20 and 30 years. Smile aesthetic parameters were measured using seven variables, and the ratios were calculated. An independent sample t-test was used to assess smile aesthetics. All seven variables namely smile width, smile height, visible dentition width, maxillary intercanine width, visible maxillary first molars, visible mandibular teeth, visible maxillary gingival margin, and the ratios between the above mentioned variables showed no detrimental effects following extraction of four first premolars on smile aesthetics.     

正畸微笑美学的影响因素及研究进展

一个完美自信的微笑可以大大提升个人的魅力。微笑美学已成为患者寻求正畸治疗的主要原因,而且是正畸医生的治疗目标。正畸医生有必要了解面部美学和当前社会对面部吸引力的偏好。正畸医生了解微笑美学的指标,可以用于指导临床操作,从而达到最佳的治疗效果。该文归纳了笑线、笑弧、颊廊、牙齿、牙龈等影响微笑美学的因素并从微笑的微观美学和迷你美学两方面作一综述。     

Smile aesthetics as perceived by dental students: a cross-sectional study

Background

An aesthetic smile has a number of components, and people generally equate a good dental appearance with success in many areas of life. The features that determine smile aesthetics could provide significant insights into post-treatment satisfaction and may predict a patient’s objectives when undergoing treatment. The purpose of this study was to evaluate how smile characteristics are perceived by dental students.

Methods

The study was performed in 431 local and international dental students at the Lithuanian University of Health Sciences. The study data were collected using a three-part questionnaire. The first part of the questionnaire included sociodemographic items, i.e., student gender, age, nationality, and years of study; the second consisted of questions about facial aesthetic features; and the third elicited responses to photographs of 17 different smiles retrieved from the Lithuanian University of Health Sciences Clinic of Orthodontics database. The smile aesthetics were evaluated according to their dentolabial, dentogingival, dental, and dental arch characteristics using a 5-point numeric rating scale (1, best; 5, worst). The data were analysed using the Pearson’s chi-square and Mann-Whitney U tests.

Results

The study included 336 local and 95 international dental students (132 men [30.6%], 299 women [69.4%]). Significantly more women than men focused on a person’s teeth when communicating (41.5% vs.32.6%, p?<?0.005). Women were more critical than men when evaluating gingival smile, the ‘golden proportion’, occlusal cant, and dental crowding. The most unfavourable smile characteristics were identified in the dental analysis category, with hypodontia ranked as the worst smile feature (mean numeric rating scale score 4.71).

Conclusion

Among dental students, the most distracting characteristics of a smile when determining its attractiveness were hypodontia, gingival smile, a reversed curvature of the occlusal plane, and dental crowding.

     

正畸患者对露龈微笑的审美认知

目的：调查成人正畸患者对露龈微笑的审美认知，并探讨医师的专业知识对正畸患者审美认知的影响。方法建立露龈微笑模型，采用电子调查问卷对正畸患者进行问卷调查。结果调查样本共计99例，露龈微笑的审美理想值-1.0 mm，可接受程度为2.0 mm。经医师对患者进行审美干预后可接受程度为2.5 mm。结论露龈微笑的理想值和可接受度可以为临床治疗提供一定的量化标准，正畸患者接受正畸专业知识干预后，对微笑显露牙龈的可接受程度增大。     

Smile attractiveness. Self-perception and influence on personality

OBJECTIVES: To investigate self-perception of smile attractiveness and to determine the role of smile line and other aspects correlated with smile attractiveness and their influence on personality traits. SUBJECTS AND METHODS: Participants judged their smile attractiveness with a patient-specific questionnaire. The questionnaire contained a spontaneous smiling photograph of the participant. Objective smile-line height was measured using a digital videographic method for smile analysis. Personality was assessed with the Dutch Personality Index. RESULTS: Cronbach's alpha for the smile judgment questionnaire was .77. The results showed that size of teeth, visibility of teeth, and upper lip position were critical factors in self-perception of smile attractiveness (social dimension). Color of teeth and gingival display were critical factors in satisfaction with smile appearance (individual dimension). Participants, smiling with teeth entirely displayed and some gingival display (two to four millimeters), perceived their smile line as most esthetic. Smiles with disproportional gingival display were judged negatively and correlated with the personality characteristics of neuroticism and self-esteem. Visibility and position of teeth correlated with dominance. CONCLUSION: The results of this research underpin the psychosocial importance and the dental significance of an attractive smile.     

数字化口腔修复（14）--冠延长术前数字化笑设计（附病例报告）

目的：通过计算机辅助设计软件,进行术前的数字化笑设计,以获得与患者的良好的沟通。方法：利用Photoshop CS6软件和CEREC?AC Omnicam 4.2软件分别对1例冠延长术术前的患者行模拟牙龈切除1 mm、2 mm和3 mm的二维和三维数字化笑设计。结果：经过患者和口腔医师共同比较二维和三维数字化笑设计的虚拟图片,双方达成共识,即牙龈切除2 mm的术后效果最为满意。数字化笑设计向患者充分预示了冠延长术后的冠宽度比、宽长比、冠根比、牙龈高点和上颌中线夹角的变化。结论：医患双方共同参与术前的二维和三维数字化笑设计是行之有效的沟通渠道和手段,同时也有利于增加术者手术的安全性和患者的满意度。     

牙冠延长术改善前牙牙龈美观效果的临床观察

目的探讨对龈-牙性露龈笑及龈缘不齐患者行牙冠延长术后的美学效果。方法对53例龈-牙性露龈笑或龈缘不齐患者共285颗患牙行牙冠延长术,用龈缘顶点水平（gingival zenith level,GZL）及微笑线水平评价治疗前后美学效果,并通过视觉模拟评分法（visual analogue scale,VAS）评价患者治疗前后的满意度。结果牙冠延长术后,患牙GZL均达到美学标准,微笑线水平符合Ⅱ、Ⅲ类美学标准,患者对牙龈美学满意度有显著性提高。结论通过正确选择适应证及精细的手术操作,龈-牙性露龈笑及龈缘不齐可通过牙冠延长术获得满意的美学效果。     

牙列中线偏斜的审美研究进展

面部对称是容貌美观的重要影响因素。在微笑美学的研究中,牙列中线与面中线的一致性与微笑审美评价结果密切相关,直接影响患者微笑的美观程度。由于牙列中线偏斜在普通人群中发生率较高,因此,牙列中线与面中线不一致常作为患者就诊的主诉,同时也是正畸医生在制定治疗计划时需要特殊考虑的一个临床诊断指标和矫治目标。本文将对牙列中线偏斜的流行病学情况、病因学分类、诊断与治疗方法及其对微笑审美的影响作一综述,以期指导临床操作。     

Influence of sex on the perception of oral and smile esthetics with different gingival display and incisal plane inclination

This study was designed to determine the esthetic perception of men and women to variations in upper and lower gingival display at smile and speech and to incisal plane tilting. Composed photographs of smile and speech with varying amounts of gingival exposure of the upper and lower teeth and gingiva at smile and at speech and with varying degrees of incisal plane tilting were rated for attractiveness by two groups of lay people. The images were presented as male or female images. A total of 300 questionnaires, including 7500 images, were evaluated by 100 subjects. The results showed that images were scored as less attractive as the amount of upper and lower gingival display was increased during smile and speech. The amount of gingival exposure graded in the esthetic range was up to one mm for the upper incisors and zero mm for the lower incisors. Incisal plane tilting was graded as unesthetic when above two degrees of deviation from the horizontal. Male and female evaluators scored images differently with upper gingival exposure. Female evaluators gave statistically significant higher scores than male evaluators to upper gingival exposure images at smile and speech of both males and females, suggesting that females are more tolerant of upper gingival exposure. Images were scored differently when presented as male or female images. Female images were scored lower by both male and female evaluators, suggesting that additional efforts should be taken in female patients to achieve an esthetic result.     

颊旁间隙对微笑美影响的研究进展

日常生活中,人们往往更关注正面微笑,正面微笑是个性、自信和魅力的体现。作为面部美学评价指标之一的颊旁间隙近年来受到了极大关注。该文就颊旁间隙对微笑美影响的研究进展做一综述,并探讨了在正畸临床中如何更好地把握颊旁间隙创造微笑美。     

62名中国汉族青年笑线水平的测量研究

目的 评估中国汉族健康人群上颌美学区域牙齿及软组织等解剖形态对容貌美观和义齿修复美学的影响,为临床牙科美学修复提供客观依据.方法 对平均年龄为28.5岁的62名旅德中国汉族青年志愿者进行面部拍照记录.依据标准的试验条件对所有志愿者大笑时上颌牙齿及其牙龈和牙龈乳头进行测量分析.统计分析采用Mann-Whitney-U检验和双因子重复测量分析.结果 所有志愿者在上唇大笑运动时81％的上颌中切牙至上颌前磨牙的牙龈形态均有不同程度显露.上颌中切牙平均显露高度为10 mm,性别间差异无统计学意义(P＞0.05).所有志愿者平均牙龈显露高度为1.3mm,平均显露牙龈乳头高度为3.4mm,男女间差异无统计学意义(P＞0.05).31％( 19/62)的志愿者为高笑线类型,50％ (31/62)的志愿者为中度笑线类型,19％ (12/62)的志愿者为低笑线类型.结论 中国汉族青年人群高笑线者比例高于西方研究人群比例,其中100％汉族青年志愿者在大笑时前牙区的牙龈乳头显露.     

Analysis of gingival margin esthetic clinical conditions by dental students

It has been suggested that one of the main factors contributing to the perception of esthetics is the position of the gingival tissues in the upper arch. The aim of this study was to evaluate the esthetic perception of dental students regarding different pictures of classical periodontal situations related to the gingival margin. This was an observational cross-sectional study involving 161 dental students. Five clinical situations defined by pictures from books were presented to the students. The cases included unchanged periodontium, gingival smile, uneven gingiva, localized gingival recession and generalized gingival recession. Esthetic perception was evaluated by a Visual Analogue Scale (VAS). The different situations were compared by One-way ANOVA, with Tukey test as post-hoc. The results showed statistically significant differences between groups (p < 0.05). The best esthetics was attributed to the periodontium without changes in shape (7.60 +/- 1.80), followed by gingival smile (6.92 +/- 2.34). The worst esthetic situation in this evaluation was the uneven gingiva (3.45 +/- 2.00). In the intermediate group are the gingival recessions. The perception of localized (5.19 +/- 1.91) and generalized (5.69 +/- 2.18) gingival recession did not differ significantly. This study concluded that different positions of the gingival tissues affect the esthetic perception of smile.     

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正畸治疗要为患者塑造美丽的笑容,对于微笑的评估和设计是很重要的,但是在临床检查中正畸医生经常忽略了微笑分析。本文综述了影响微笑美的主要因素,探讨了其在正畸诊断、矫治设计及治疗中的重要性。