Peculiarities of visual perception of dentition and smile aesthetic parameters

As the result of the studies it was determined in which limits the dentition central line displacement from the face middle line and the change of smile line tilt angle become noticeable for visual perception. And also how much visual perception of the dentition aesthetic parameters were differed in doctors with different experience, dental technicians and patients.     

正畸患者对女性上颌中切牙和侧切牙牙龈高度不对称的审美评价

目的：调查正畸患者对女性上颌中切牙和侧切牙牙龈高度变化的关注程度和审美评价。方法建立女性上颌中切牙和侧切牙牙龈向切端偏移的模型（上颌中切牙和侧切牙牙龈向切端偏移0.5 mm、1.0 mm、1.5 mm和2 mm）,利用调查问卷对正畸患者进行调查。结果上颌中切牙和侧切牙左右牙龈对称和上颌中切牙牙龈向切端偏移0.5 mm时,是患者认为最美观的笑容;上颌中切牙和侧切牙牙龈向切端偏移1.0 mm时,患者开始察觉上颌中切牙和侧切牙牙龈不对称（P<0.05）;上颌中切牙和侧切牙牙龈向切端偏移1.5 mm到2.0 mm时,患者认为已经影响了美观和笑容（P<0.05）。结论上颌中切牙和侧切牙牙龈不对称的牙龈高度变化1.0 mm到1.5 mm以上时,患者开始察觉和开始认为影响了美观和笑容。     

Perception of Saudi dentists and lay people to altered smile esthetics

Aim

To evaluate and compare the perceptions of Saudi dentists and lay people to altered smile features.

Methods

Thirty-six digital smile photographs with altered features were used. Altered features included the following: crown length, width, gingival level of the lateral incisors, gingival display, midline diastema, and upper midline shift. The photographs were presented to a sample of 30 dentists and 30 lay people with equal gender distribution. Each participant rated each picture with a visual analogue scale, which ranged from 0 (very unattractive) to 100 (very attractive).

Results

Dentists were more critical than lay people when evaluating symmetrical crown length discrepancies. Compared to lay people, Saudi dentists gave lower ratings to a crown length discrepancy of >2 mm (P < 0.001), crown width discrepancy of ⩾2 mm (P < 0.05), change in gingiva to lip distance of ⩾2 mm (P < 0.01), and midline deviation of >1 mm (P < 0.01). There was no significant difference between dentists and lay people towards alterations in the gingival level of the lateral incisors or towards a space between the central incisors. No significant sex difference was seen across the groups.

Conclusion

In this sample, Saudi dentists gave significantly lower attractiveness scores to crown length and crown width discrepancies, midline deviations, and changes in gingiva to lip distance compared to Saudi lay people.     

Children's perceptions of smile esthetics and their influence on social judgment

Objective:To define a threshold of acceptance of smile esthetics for children and adolescents.Materials and Methods:A systematic search in the medical literature (PubMed, PubMed Central, National Library of Medicine''s Medline, Embase, Cochrane Central Register of Controlled Clinical Trials, Web of Knowledge, Scopus, Google Scholar, and LILACs) was performed to identify all peer-reviewed papers reporting data regarding the evaluation of children''s and adolescents'' perceptions of dental esthetic factors. The search was conducted using a research strategy based on keywords such as “children,” “adolescents,” “smile aesthetics perception,” “smile aesthetics evaluation.” Studies analyzing smile esthetics involving at least 10 observers younger than 18 years of age were selected.Results:Among the 1667 analyzed articles, five studies were selected for the final review process. No study included in the review analyzed perception of smile anomalies in a quantitative or qualitative way, thus no threshold was identified for smile features. Among the analyzed samples, unaltered smiles were always significantly associated with better evaluation scores when compared with altered smiles.Conclusions:Smile esthetics influence social perception during childhood and adolescence. However, thresholds of smile esthetic acceptance in children and adolescents are still not available.     

Influence of lower facial height changes on frontal facial attractiveness and perception of treatment need by lay people

Objective:To test the hypothesis that lower facial height has no influence on frontal facial attractiveness and treatment need perception of lay people.Materials and Methods:Frontal facial silhouettes of a man and a woman with normal lower facial height values (male: 81.5 mm; female: 70.5 mm) were modified by increasing and decreasing their lower facial heights in steps of 1 mm to obtain frontal images with different lower facial height alterations ranging from +6 mm to −6 mm for each sex. A panel of 100 lay people scored each silhouette''s attractiveness on a 100-mm visual analogue scale (VAS) and also indicated whether they would seek treatment if the image represented their own. The Wilcoxon signed rank test was used to compare the VAS scores.Results:Unaltered ±1-mm and ±2-mm silhouettes got the highest VAS scores. Scores were significantly lower (P ≤ .001) as the divergence from the normal value exceeded 2 mm. Beyond +3 mm and −4 mm in females and +4 mm and −3 mm in males the difference between the scores became statistically insignificant. At ±4 mm, more than 75% of the raters elected to have treatment.Conclusion:The hypothesis was rejected.     

非洛地平致牙龈增生3例报告及相关文献复习

本文报告了3例因服用非洛地平而致牙龈增生的病例,在停用(或减量)该药物及牙周治疗后,牙龈增生消退,形态恢复正常。作者复习了相关文献,并对药物性牙龈增生的发生机制和预防治疗进行了讨论。     

Esthetics and smile characteristics evaluated by laypersons: A comparison of Canadian and US data

Objective:To collect data regarding Canadian laypersons'' perceptions of smile esthetics and compare these data to US data in order to evaluate cultural differences.Materials and Methods:Using Adobe Photoshop 7, a digital image of a posed smile of a sexually ambiguous lower face was prepared so that hard and soft tissue could be manipulated to alter buccal corridor (BC), gingival display (GD), occlusal cant (OC), maxillary midline to face discrepancy (MMFD), and lateral central gingival discrepancy (LCGD). Adult Canadian laypersons (n  =  103) completed an interactive computer-based survey of 29 randomized images to compare smile preferences for these variables. The custom survey was developed to display fluid, continuously appearing modifiable smile variables using MATLAB R2008 for presentation. These data were compared with previously published data for US laypersons. Statistical inference was determined using Wilcoxon rank sum tests.Results:Canadian laypersons were more sensitive in detecting deviations from ideal and had a narrower range of acceptability thresholds for BC, GD, OC, MMFD, and LCGD. Ideal esthetic values were significantly different only for BC.Conclusions:It appears that cultural differences do exist related to smile characteristics. Clinically significant differences in the preference of the smile characteristics were found between Canadian and US laypersons. Canadian laypersons, on average, were more discriminating to deviations from ideal and had a narrower range of acceptability.     

The influence of visible dental caries on social judgements and overall facial attractiveness amongst undergraduates

Objectives

Where previous work has suggested that the presence of caries alone may influence social judgements, this study investigated whether overall facial attractiveness and caries influence ratings of social and intellectual competence and the extent to which any effect may be the result of facial attractiveness alone.

Methods

Three photos of young males who were reliably rated as ‘unattractive’, ‘attractive’ or ‘neither unattractive nor attractive’, were selected and were digitally modified by a dentist to have caries or not, to give a total of 6 vignettes. In a cross-sectional study of N = 263 undergraduates, each participant appraised one single colour photograph for the following characteristics: social competence, intellectual ability, psychological adjustment, care of own appearance and attractiveness, using a 5 point Likert scale.

Results

The data were analysed using two-way ANOVA where factor 1 was attractiveness and factor 2 was the presence or absence of caries. Faces of higher attractiveness received significantly more positive appraisals than those of lower attractiveness on all measures, irrespective of caries. Presence of caries only resulted in significant decreases in measures of attractiveness and care of own appearance, but none of the other measures.

Conclusions

Individuals’ overall level of attractiveness is more important to a social judgement than their dental condition. Previous research in this area may have found significant effects for dental condition due to using a single face with more marked differences in caries, which affected facial attractiveness. Future research should focus on factors that affect attractiveness and how these compete to affect social judgments.     

数字化微笑设计在前牙美学修复中的应用及研究进展

数字化微笑设计作为口腔美学的基础性程序,已被越来越多的口腔医生用于临床诊断和治疗,可与传统模型技术及其他数字化技术相结合,促进医患、医技、医医的交流沟通,显著提高治疗的精准性、可预测性、实施效率及成功率。数字化微笑设计除了广泛应用于口腔修复领域,还可联合牙周、正畸、颌面外科等学科进行综合治疗。该文就数字化微笑设计在前牙美学修复中应用的现状及发展作一综述。     

Effect of smile index and incisal edge position on perception of attractiveness in different age groups

Changes in occlusal vertical dimension (OVD) and age have been found to affect Smile Index (SI, width/height of smile). Limited information is available regarding the aesthetic effects of these changes. The objective of this study was to evaluate the attractiveness of digitally manipulated smile images with differences in SI and incisal edge position (IEP) judged by respondents in different age groups. A total of 12 smile images were generated with varying SI (3·5, 5·3, 7·2, 9·0) and IEP (High, Medium, Low). Fifty respondents each in four age groups (15–24, 25–39, 40–54, 55+) evaluated the attractiveness of the 12 images using a 0–10 visual analog scale (VAS, 10 being most attractive). A repeated‐measures three‐factorial mixed model assessed differences. SI, IEP and age of respondents were found to significantly influence attractiveness score (P < 0·01 for all). With all age groups combined, SI = 7·2/IEP = Medium was most attractive (VAS = 7·22), followed by SI = 9·0/IEP = Medium, and SI = 5·3/IEP = Medium (VAS = 6·53 and 6·48, respectively). SI = 3·5/IEP = High and SI = 3·5/IEP = Low were least attractive (VAS = 1·99 and VAS = 2·58, respectively). Age group significantly influenced aesthetic perception, with younger respondents more critical in differences in SI and IEP. SI and IEP significantly influenced attractiveness of the smile in all respondent age groups. Low SI (i.e. 3·5) combined with high or low IEP was unattractive. Medium SI to high SI (i.e. 5·3–9·0) combined with medium IEP were considered attractive.     

不同类型正畸患者对颜面美感知的差异及相关因素研究

目的：调查不同类型的正畸患者对颜面美的感知差异,为正畸医师进行诊断设计提供美学参考。方法：选取45例初诊患者的面像（正面像、正面微笑像、侧面像、正面咬合像）制作调查问卷。另随机选取213例正畸患者在治疗前对问卷中病例资料的颜面美进行评价,进行统计学分析。结果：①．性别、年龄、文化程度等因素会影响患者对颜面美的感知度,婚姻状况对患者颜面美的感知影响不明显。中青年、女性、文化程度较高者比少年、男性、文化程度较低者对颜面美的感知度相对较高。②．正畸患者对安氏Ⅲ类病例颜面美的评价最低,其次是安氏Ⅱ1类病例,对安氏Ⅱ2类、安氏I类病例的美学评价较高。结论：不同背景患者对颜面美的感知度不同,提示进行正畸治疗前应充分了解患者的美学倾向,制定个性化的矫治方案。     

弯制卡环与铸造卡环对龈下微生物的影响

目的了解卡环戴入前后基牙龈下微生物变化,考察弯制卡环与铸造卡环对龈下微生物影响的差异.方法检查戴牙前、戴牙后1周、1月和3月,弯制卡环和铸造卡环所在基牙龈下可培养细菌总量及革兰氏阴性菌构成比的变化.结果与戴牙前相比,戴牙后1周、1月和3月龈下可培养细菌总量及革兰氏阴性菌构成比均明显增加,差异有统计学意义(P＜0.05),戴牙后1月,弯制卡环与铸造卡环所在基牙龈下革兰氏阴性菌构成比有统计学差异(P＜0.05).结论在本文观察期(3个月)内,卡环的戴入造成龈下微生物中革兰氏阴性菌构成比显著增加,弯制卡环与铸造卡环对龈下微生物中革兰氏阴性菌构成比的影响没有显著差异.     

The influence of a dentifrice containing a zinc salt and a nonionic antimicrobial agent on the maintenance of gingival helath

The purpose of the present investigation was to test the concept that a dentifrice containing zinc citrate and Triclosan could maintain gingival health. The gingival health of 101 young predominately female student nurses in Oslo was brought to a high level by professional cleaning supported by oral hygiene instruction. The criterion of gingival health was less than or equal to 5 elicited bleeding sites from a full mouth assessment. The mean bleeding value attained for the whole group was 3.5. 2 balanced groups were formed, based on the initial number of elicited bleeding sites and plaque values. One group used the test dentifrice and the other group the placebo for 6 months, with an intermediate assessment after 3 months. The placebo group failed to maintain the standard of oral hygiene and gingival health that had been achieved by professional care. In contrast, the group using the test dentifrice for 6 months exhibited similar levels of plaque and gingival health to that observed at baseline following oral hygiene instruction. After 6 months, less than 7% of the subjects in the placebo group possessed healthy gingivae in contrast to 60% of the test group. Thus a dentifrice containing a zinc salt and nonionic germicide had successfully maintained gingival health in a group of young adults.