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。     

颊旁间隙与颅颌面组织结构的相关性研究

目的　探讨影响颊旁间隙大小的颅颌面软硬组织因素，为正畸临床诊断分析和治疗设计提供参考。方法  选取个别正常牙合、五官端正的学生30名，采集其姿势位微笑面像、上颌牙列模型及X线头颅定位侧位片，获得各项颅颌面软硬组织评估参数。然后采用SPSS 17.0统计分析软件对数据进行Spearman相关性检验和多重线性回归分析。结果　Spearman相关性检验结果显示，上中切牙长轴与鼻根点-上齿槽座点连线的交角（U1-NA）、下中切牙长轴与下颌平面相交之上内角（L1-MP）、下中切牙长轴与鼻根点-下齿槽座点连线的交角（L1-NB）、下颌平面角（MP-FH）、下面高（ANS-Me）、鼻下点到软组织颏下点距离（Sn-Mes）、上唇垂直高度（Sn-Stms）、下唇下缘点到软组织颏下点距离（Stms-Me）、U1暴露量以及上颌前磨牙区宽度与颊旁间隙比例有相关性（P＜0.05）。多重线性回归分析结果显示，Sn-Mes、U1暴露量以及上颌前磨牙区宽度对颊旁间隙比例的影响有统计学意义（P＜0.05）。 结论　随着下面高、微笑时上切牙暴露量以及上颌前磨牙区宽度的增加，颊旁区有减小的趋势。     

正面微笑的美学研究

微笑是开心时情感的自然流露,越来越多的口腔正畸医生把微笑美作为矫治目标之一.如何才能让患者拥有最自信、最迷人的微笑,成为众多口腔正畸医生所关注的问题.影响微笑美的因素较多,它是水平向和垂直向以及时间等多种因素共同作用的结果.只有充分了解影响和制约微笑美的各种因素,才能真正做到让患者拥有迷人的微笑.本文就正面微笑的美学研究作一综述.     

微笑美学基础知识教育对大学生主观感知变化的影响

目的 了解大学生对微笑美学基础知识的了解程度以及需求现状.方法 随机选取120名在读大学生进行问卷调查.在120受试者中随机抽选男女各20位,进行微笑基础知识教育,1周后随访调查.取受试者干预前后2次正面微笑照片被男女各10名大众参与者进行主观评价.结果 从各个问题答案构成比中看出,男女各占比例相差小,但微笑美学基础知识在大学生中迫切需要学习.卡方检验显示受检者主观感知变化结果:对微笑美学基础知识了解改变,干预具有一定效果;专业指导与训练后会变得更好,男性改变明显,女性选择“可能性”的非常多;估计自己微笑理想程度以0～10分的中点5分处分界,对评分数据分析,显示出尚不能认为女性变化明显但整体主观变化明显.大众评价结果显示,尚不能认为女性评价者认为授课后的相片更好看;而男性评价者认为授课后的相片更好看;男女共20名评价结果显示,更倾向于授课后的相片好看.结论 当今大学生迫切需要微笑美学知识这方面的教育,需要进一步发挥正畸医师的社会性作用,即将微笑美学知识面向社会推广.     

正畸可控的笑容特征指标对微笑美的影响研究

目的 探讨各项正畸可控的笑容特征指标与微笑美的相关性。方法 选取男女微笑时面下1/3照片各1张,利用Photoshop依据各指标（切牙暴露量、露龈量、笑弧、颊廊、上颌牙合平面倾斜度及上切牙下唇间距）分别进行变动,选择200名大学生对其进行评价。数据输入Spss 19.0 统计软件包,将每项指标对应各图得分与该指标的变化进行等级资料Spearman相关分析。结果 男女笑容图的得分均与切牙暴露量、笑弧一致性成正相关（P<0.05）,与露龈量、颊廊面积、上颌牙合平面倾斜度、上切牙下唇间距成负相关（P<0.05）。结论 唇齿龈的相对位置对笑容的美观有显著影响,正畸过程中应注意调控。     

44例颞下咽旁间隙肿瘤的临床和治疗

颞下咽旁间隙肿瘤患者４４例。良性肿瘤３１例，起源最多是腮腺深叶，其次是神经鞘膜；恶性肿瘤１３例，种类繁多。临床主要表现为咽侧壁膨隆；大多数病人是一种多样化、无痛性肿胀，少数病人出现发音改变和吞咽困难。全部病例获手术治疗。其中４１例获随访结果，随访时间最长２０年，作者就颞下咽旁间隙肿瘤的临床表现、诊断和手术等问题进行了讨论。     

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。     

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。     

正畸治疗对微笑面孔审美认知影响的功能磁共振研究

目的采用脑功能磁共振成像(fMRI)技术探究正常成人对正畸治疗前后面孔审美认知的脑激活模式。方法以96张不同吸引力正畸治疗前后的微笑面孔作为刺激材料,在20名健康志愿者对微笑面孔进行审美评价的同时利用fMRI进行全脑数据采集,用SPM8软件处理功能成像数据,分析不同面孔刺激的脑区激活情况。结果枕叶、颞叶、梭状回等脑区参与了正畸前后面孔审美的认知过程。对于高吸引力组面孔,正畸前较正畸后显著激活右侧额内侧回、右侧额中回、右侧中央前回;对于低吸引力组,正畸前较正畸后显著激活右侧旁中央小叶、右侧顶下小叶、左侧颞中回、双侧扣带回、左侧楔前叶。结论多个功能脑区协同参与了正畸前后面孔的审美认知过程,正畸前面孔相对于正畸后面孔显著引起认知、注意、情绪相关脑区的激活改变。     

Analysis of smile esthetics in American Board of Orthodontic patients

Objective:To investigate the common denominators of an esthetically pleasing smile in patients who were considered to be successfully treated upon the submission to American Board Orthodontics (ABO) clinical examination.Material and Methods:A total of 462 patients were examined. Ninety subjects that fulfilled the inclusion criteria were included. Standardized digital smile photographs of the subjects were rated by 30 panel members, including orthodontists, general dentists, and parents of orthodontic patients, using a numeric version of the visual analog scale. Three groups were formed using the mean esthetic score ± standard deviation range: unattractive (n  =  21), average (n  =  47), and attractive (n  =  22) smiles. Eleven smile characteristics were digitally measured on the photographs and compared between the groups using one-way analysis of variance and χ² tests. Additionally, regression analyses were used to investigate the association of the smile characteristics with the esthetic score.Results:A significant difference was found between the three groups for the comparison of smile arc relationship (P < .001). When all the variables used in this study were entered in the regression analysis, a positive association was found (r  =  0.658; r²  =  0.434; P < .001). Additionally, two models were defined using stepwise regression. The first model included the smile arc (r  =  0.478; r²  =  0.228; P < .001), and the second model had both the smile arc and right gingival display/visible dentition display ratio (r  =  0.567; r²  =  0.321; P < .001).Conclusions:A harmonious smile arc relationship and less gingival display during a smile are significantly associated with smile attractiveness in patients considered successfully treated according to ABO standards.     

Clinical photography vs digital video clips for the assessment of smile esthetics

Objective: To test the null hypothesis that there is no clinically significant difference between the post–orthodontic treatment images of smiles of subjects captured by clinical photography and the smiles of the same subjects obtained from digital video clips.Materials and Methods:Clinical photographs and digital video captures were obtained from 48 orthodontically treated patients. An updated version of the Smile Mesh^TM program was used to quantify and compare smile characteristics obtained with the two methods. A paired-samples t-test was performed to test for mean differences in Smile Mesh measurements generated from both smile images. The relationship between the various Smile Mesh measurements obtained from both smile images was examined by way of Pearson product-moment correlation.Results:A significant difference was found between 7 of the 14 mean Smile Mesh measurements. The absolute values of all these differences, however, were smaller than 1 mm and therefore were not clinically significant. With the exception of lower lip to maxillary incisor, all measurements showed a moderate to strong relation with each other (P values ranging from .47 to .82; P < .001).Conclusions:The hypothesis cannot be rejected. A significant positive correlation was noted between Smile Mesh measurements obtained from smiles captured by clinical photography and those captured with digital video clips. This supports the conclusion that a standard digital photograph appears to be a valid tool for analysis of the posttreatment smile.     

The effects of buccal corridor spaces and arch form on smile esthetics.

PURPOSE: An attractive, well-balanced smile is a paramount treatment objective of modern orthodontic therapy. The purpose of this study was to determine the effects of buccal corridor spaces (BCS) and arch form on smile esthetics as perceived by laypeople, general dentists, and orthodontists. MATERIAL: Photographs of 20 women treated by 2 orthodontists were collected: 1 group had narrow tapered or tapered arch forms, and the other had normal to broad arch forms. Photographs of 10 untreated women served as a control sample. All photographs showed the subjects smiling. The photographs were digitized and evaluated for BCS. Then, photographs with BCS were altered to eliminate the dark triangular areas, and those without BCS were altered by the addition of dark triangular areas at the lateral aspects of the smile. The altered photographs were randomized into a survey with the 30 original photographs. Three groups of raters (dentists, orthodontists, and laypeople) used a visual analogue scale to rate the photographs. RESULTS: There was no significant difference in smile scores related to BCS for all samples and for all viewers. Dentists rated broader arch forms as more esthetic than untreated arch forms. Orthodontists rated broader arch forms as more esthetic than narrow tapered arch forms and untreated arch forms. Lay people showed no preference of arch form. CONCLUSIONS: This study demonstrates that the presence of BCS does not influence smile esthetics. However, there are differences in how dentists, orthodontists, and laypeople evaluate smiles and in what arch form each group prefers.     

Maxillary arch width and buccal corridor changes with Damon and conventional brackets: A retrospective analysis

Objective:To evaluate the effect of Damon self-ligating and conventional bracket systems on buccal corridor widths and areas.Materials and Methods:A retrospective sample of consecutively treated patients using either conventional (CG, n  =  45) or Damon self-ligating (SL, n  =  39) brackets was analyzed to determine any differences in buccal corridor widths and areas both within and between groups. Pretreatment and posttreatment frontal photographs were transferred to Photoshop CC, standardized using intercanthal width, and linear and area measurements were performed with tools in Photoshop CC. Ratios were then calculated for statistical analysis. Relationships between arch widths and buccal corridors were also examined.Results:There were no significant differences in the posttreatment intercanine or intermolar widths either within or between the CG and SL groups. There were no significant differences in any buccal corridor width or area measurement either within or between the CG and SL groups. There were strong correlations with the intercanine width and the corresponding buccal corridor smile width measurements. There was an inverse correlation with the buccal corridor area in relation to the canine and the total smile width.Conclusions:It is likely that posttreatment increases in arch width can be seen in patients treated with either a conventional bracket system or the Damon system. It is highly unlikely that there is any significant difference in buccal corridor width or area in patients treated with the Damon self-ligating system or a conventional bracket system.     

Improvement in smile esthetics following orthodontic treatment: A retrospective study utilizing standardized smile analysis

Objective:To quantify smile esthetics following orthodontic treatment and determine whether these changes are correlated to the severity of the initial malocclusion.Materials and Methods:A standardized smile mesh analysis that evaluated nine lip-tooth characteristics was applied to two groups of successfully treated patients: group 1 (initial American Board of Orthodontics Discrepancy Index [DI] score <20) and group 2 (initial DI score >20). T-tests were used to detect significant differences between the low-DI and high-DI groups for baseline pretreatment measurements, baseline posttreatment measurements, and changes from pre- to posttreatment. A Spearman correlation test compared the initial DI values with the changes in the nine smile measurements.Results:Five of the smile measurements were improved in both groups following orthodontic treatment. Both groups demonstrated improved incisor exposure, an improved gingival smile line, an increase in smile width, a decreased buccal corridor space, and an improvement in smile consonance. Spearman correlation tests showed that initial DI value was not correlated to changes in any of the individual smile measurements.Conclusions:Smile esthetics is improved by orthodontic treatment regardless of the initial severity of the malocclusion. In other words, patients with more complex orthodontic issues and their counterparts with minor malocclusions benefitted equally from treatment in terms of their smile esthetics.     

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.     

自然微笑分析方法的建立及其初步应用研究

目的 基于高清数码摄像结合计算机图像测量技术建立自然微笑分析方法,初步探索汉族女性青年微笑相关基础数据,为提高口腔治疗的美学效果提供参考依据.方法 通过高清数码摄像技术获取自然微笑全过程,并结合计算机图像分析和测量技术建立自然微笑分析方法;选择牙龈健康、年龄20 ～ 30岁汉族女青年99人,应用该方法获得微笑类型分布、唇切距离、牙龈显露量等微笑相关指标的基础性数据,并进行统计学分析.结果 建立了一种标准、客观的自然微笑分析方法;99名汉族女青年中高位、中位微笑类型均占43％ (43/99),低位微笑类型占13％ (13/99);高位微笑者微笑时显露的牙龈量均值为(1.34±0.98) mm.结论 初步建立了基于计算机图像测量技术的自然微笑分析方法;本项研究中大多数汉族女青年表现为中、高位微笑类型.     

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.