A comparative assessment of the perception of Chinese facial profile esthetics

INTRODUCTION: The aim of this study was to compare the perception of male and female Chinese facial profile esthetics between dental professionals, dental students, and laypersons. MATERIAL: The sample comprised 31 dental professionals (20 orthodontists, 11 oral surgeons), 92 dental students, and 152 laypersons in an Asian community. The facial profile photographs and lateral cephalometric radiographs of a Chinese man and a woman, each with a normal profile, a Class I incisor relationship, and a Class I skeletal pattern, were digitized. The digital images were modified to obtain 7 facial profiles for each sex. The images were constructed by altering cephalometric skeletal and dental hard tissue Chinese normative values by 2 standard deviations in the anteroposterior plane only. The 7 profiles were (1) bimaxillary protrusion, (2) protrusive mandible, (3) retrusive mandible, (4) normal profile (Class I incisor with Class I skeletal pattern), (5) retrusive maxilla, (6) protrusive maxilla, and (7) bimaxillary retrusion. RESULTS: Normal and bimaxillary retrusion Chinese male and female profiles were perceived to be highly attractive by all 3 groups. Profiles with a protrusive mandible were perceived to be the least attractive. Dental professionals, dental students, and laypersons were highly correlated for the perception of male (r > 0.67) and female (r > 0.93) profile esthetics. All correlation coefficients were found to be significant for the perception of female profiles, but, for male profiles, only the correlation coefficient between dental students and laypersons was significant. CONCLUSIONS: Chinese male and female profiles that were normal or had bimaxillary retrusion were perceived to be highly attractive by dental professionals, dental students, and laypersons, and profiles with a protrusive mandible were perceived to be the least attractive. Dental students and laypersons were more tolerant of a male profile with a retrusive mandible than were dental professionals, and all groups were more tolerant of bimaxillary protrusion in women than in men. Dental professionals, dental students, and laypersons had a similar trend in male and female esthetic preferences. The perception of female profiles by all 3 groups was highly and significantly correlated. Only the perception of male esthetics by dental students and laypersons was not significantly correlated with dental professionals.     

Professional assessment of facial profile attractiveness.

INTRODUCTION: The aim of this study was to compare the assessments of Chinese facial profile attractiveness by orthodontists and oral surgeons. METHODS: The sample comprised 31 dental professionals (20 orthodontists, 11 oral surgeons) in an Asian community. Facial profile photographs and lateral cephalometric radiographs of 2 Chinese adults (1 man, 1 woman) with normal profiles, Class I incisor relationships, and Class I skeletal patterns were digitized. The digital images were modified by altering cephalometric skeletal and dental hard tissue Chinese normative values in increments of 2 standard deviations in the anteroposterior plane to obtain 7 facial profiles for each sex. The images were bimaxillary protrusion, protrusive mandible, retrusive mandible, normal profile (Class I incisor with Class I skeletal pattern), retrusive maxilla, protrusive maxilla, and bimaxillary retrusion. The Mann-Whitney U test was used to determine professional differences in assessment. Multiple regression analysis was performed with age, professional status, sex, and number of years in practice as independent variables. RESULTS AND CONCLUSIONS: A strong correlation was found in the profile assessment between orthodontists and oral surgeons. Normal and bimaxillary retrusive Chinese male and female profiles were judged to be highly attractive by orthodontists and oral surgeons. Chinese male and female profiles with protrusive mandibles were judged the least attractive. There was a difference in professional opinion about the most attractive male profile (P < .05), with orthodontists preferring a flatter profile and oral surgeons preferring a fuller normal Chinese profile. Sex of dental professionals and number of years in clinical practice were found to affect profile rankings.     

高角型双颌前突矫治前后软硬组织改变分析

目的探讨正畸治疗对高角型双颌前突患者软硬组织矢状及垂直向的影响。方法对18例高角型双颌前突患者在拔除4个第一前磨牙后,采用直丝弓矫治技术进行矫治。矫治前后拍摄X线头颅侧位定位片,并对矫治前后软硬组织侧貌的变化进行分析。结果①上下颌骨矢状及垂直向关系无明显变化;②上下前牙突度和倾斜度明显减小;③上下磨牙垂直向及矢状向支抗得到较好控制,牙合平面角无明显改变;④上下唇突度明显减小,上唇长度加长,下唇长度减小。颏厚度增加1.70mm,颏唇沟加深1.13 mm。结论高角型双颌前突患者拔牙矫治后垂直向及矢状向支抗可得到较好控制,侧貌有明显改善。     

上海地区颜面侧貌审美评估的研究

目的研究上海地区公众对颜面侧貌审美的评估,为临床正畸等治疗效果提供参考。方法选取上海地区可接受面型的男女模特各一名,用Maya 6.0软件三维重建其侧貌,参照Mantzikos分类法变化得出男女侧貌像各5幅。选择不同年龄、性别、职业、学历的上海地区居民共321名,对上述侧貌像进行评估。结果显示上海地区现代男女侧貌都以双颌稍突面型为最佳,其次是可接受面型,不受欢迎的男性是双颌或下颌较后缩的面型;女性则是双颌或下颌较后缩的及下颌较前突的面型。结论上海地区男女面型都以双颌稍突的为最易接受的,其次是可接受面型,不受欢迎的面型有所不同,男性面型和女性面型在审美上存在一定差异;个体对颜面侧貌审美不受性别影响,职业、年龄及文化程度虽有影响,但不起决定性作用;Maya 6.0三维软件对颜面侧貌研究有实用价值。     

成人双颌前突错畸形患者拔牙正畸治疗后颅面软硬组织的变化

目的探讨双颌前突错[牙合]畸形成人患者拔牙矫治后软硬组织的变化。方法选取16例双颌前突错[牙合]畸形成人患者．均于拔牙后应用直丝弓或方丝弓技术进行矫治．并做治疗前后X线头颅侧位定位片测量,以分析治疗前后软硬组织的变化。结果（1）上下颌骨间关系无明显变化[SNA、SNB、ANB变化无统计学意义（P〉0．05）];（2）L1-MP、UI-LI、U1-NA、L1-NB前后差异均有统计学意义（P〈O．01）．上下前牙突度和倾斜度明显减小;（3）颏厚（Pos-Po）、鼻唇角（Cm—Sn—Ls）、面凸角（N＇-Sn-Pg’）、上唇厚（UL-UI）、下唇厚（LL-LI）、上下唇角（A’UL-B’-LL）治疗后显著增大,鼻、唇、颏的协调关系得以明显改善。结论双颌前突错[牙合]畸形成人患者拔牙矫正后,切牙后移可以改善双颌前突侧貌和唇的闭合功能,但对骨骼作用不明显。     

Correlation between objective and subjective evaluation of profile in bimaxillary protrusion patients after orthodontic treatment

Objective:To correlate the objective cephalometric measurements with subjective facial esthetics in patients with bimaxillary protrusion.Materials and Methods:The sample consisted of 60 Asian-Chinese patients with bimaxillary protrusion who met the inclusion criteria. The facial esthetics of posttreatment profile and the change of profile on standardized lateral photographs were rated by a panel of 10 orthodontists and a panel of 10 lay persons with bimaxillary protrusion. All of the pretreatment and posttreatment cephalograms were digitized and traced. Twenty-five cephalometric measurements were constructed and analyzed. Correlations between the subjective facial esthetic scores and each cephalometric measurement were evaluated.Results:The cephalometric measurements correlated with the facial esthetic scores of posttreatment profile given by the orthodontist and the lay persons were basically the same. For the evaluation of posttreatment profile in bimaxillary protrusion patients, the upper and lower lip to E-line, upper and lower incisor tip to AP plane, Pg-NB distance, mentolabial angle, and sulcus depth correlated significantly with the esthetic score. For the evaluation of profile change during orthodontic treatment, retraction of upper incisor relative to AP plane or the perpendicular line through sella (line Y), change of upper incisor inclination, change of mentolabial sulcus depth, and retraction of lips relative to E-line were correlated positively with the esthetic value.Conclusions:Cephalometric measurements of lip position, incisor position, and chin morphology were key parameters correlated to facial esthetics.     

Comparison of Perceptions of Computer-Animated Left- and Right-Facing Profiles

PURPOSE: Although scientific publications differ in displaying left- or right-facing profiles, there are few systematic studies of the possible effects of directional biases and laterality on patients' and clinicians' perceptions of treatment need, outcomes, and satisfaction. As part of a research program to quantitate the physical bases of the perceived zone of acceptability and most-pleasing facial profiles, responses to computer-animated left- and right-facing soft-tissue profile images were compared and related to eye and hand preference. MATERIALS AND METHODS: Standardized left-facing, soft-tissue profile images were captured in color and digitized. The right-facing profile was created by reversing the left profile image to display a mirror image. Using imaging and customized morphing software, retrusive and protrusive extremes were created, from which transitional frames were developed to display five features of the soft-tissue profile: upper lip, chin, bimaxillary position, lower face height, and mandible. One left- and one right-facing profile for a Class II division 1 female, and Class III male were randomly presented to 24 subjects who were asked to indicate: 1) acceptability by pressing a mouse button and releasing the button when the images were no longer acceptable; and 2) most-pleasing image by pressing the mouse button once. RESULTS: No differences were found between left- and right-profile images for zone of acceptability, midpoint of the zone of acceptability, or most pleasing; nor was there any relation to laterality measures. However, consistently higher intercorrelations among the features for the zone of acceptability were found for the left- than for the right-facing profiles for retrusive to protrusive and protrusive to retrusive excursions measured in millimeters (p < .001). The bimaxillary position accounted for most of the variance in judgments of acceptability with greater influence on the left than on the right profile. CONCLUSION: With the increasing use of computer-imaging in dental practices, the influence of psychophysical and other environmental variables on perception must be considered.     

The perception of facial aesthetics in a young Spanish population

Improved facial aesthetics is one aim of orthodontic treatment. This study was designed to determine if the faces considered more beautiful in a young population exhibit the same parameters used by orthodontists to assess successful results. A panel of 34 laypeople (30 females and 4 males) evaluated a set containing one frontal, one frontal during smiling, and one profile photograph of 89 students (77 females and 12 males) on a 5-point attractiveness scale, in relation to a set of reference photographs. For each photographic set, the mean and final scores were calculated. Once the sample was established, 11 subjects (9 females and 2 males) with the highest final facial aesthetic score were selected and cephalometric analysis was performed. All cephalometric measurements were within the norm for the total sample. When the sample was divided by gender, Wilcoxon's W non-parametric test showed significant differences between the male and female photographs; while females tended to a Class II malocclusion, with the mandible slightly retrusive to the maxilla, males tended to a Class III and showed a straighter profile with a prominent chin; the face height ratio was higher in males. There were no significant differences between genders for lower lip to E plane. The findings show that the faces considered more attractive fulfilled the cephalometric and facial norms.     

微种植体支抗远中移动上、下牙列矫治成人双牙弓前突15例临床分析

目的通过对患者治疗前、后X线头影测量分析,探讨利用微钛钉种植体支抗牵引上、下牙列,整体远中移动矫治成人轻、中度双牙弓前突的新途径。方法15例双牙弓轻、中度前突的成年患者,拔除第三恒磨牙,上颌种植钉植入颧牙槽嵴,下颌种植钉植入内、外斜线颊棚区,利用镍钛螺旋弹簧牵引上、下牙列,整体向远中移动。对所有病例矫治前、后的头颅定位侧位片、全口曲面体层片进行测量,采用SPSS13.0软件包对所得数据进行统计学分析。结果①60颗微钛钉种植体均保持稳固。②SNA、SNB等骨骼方面的测量值矫治前、后无显著改变（P>0.05）;U1/NA、U1-NA、L1/NB 、L1-NB、U1/L1的变化差异具有显著性（P<0.05）,表明上、下前牙突度和倾斜度明显减小。③鼻唇角（Cm-Sn-UL）、颏唇沟角（LL-B’-Pos）治疗后显著增大（P<0.01）,上、下唇相对于审美平面的突度减小,鼻、唇、颏的协调关系明显改善,面部侧貌改善。④上、下颌磨牙、切牙均不同程度远中移动。结论微钛钉种植体能提供稳定的支抗,牵引上、下牙列整体远中移动,矫治成人轻、中度双牙弓前突,硬组织和软组织均发生明显变化。     

Characterization of phenotypes of skeletal Class III malocclusion in Korean adult patients treated with orthognathic surgery using cluster analysis

ObjectivesTo characterize the phenotypes of skeletal Class III malocclusion in adult patients who underwent orthognathic surgery (OGS).Materials and MethodsThe sample consisted of 326 patients with Class III malocclusion treated with OGS (170 men and 156 women; mean age, 22.2 years). Using lateral cephalograms taken at initial visits, 13 angular variables and one ratio cephalometric variable were measured. Using three representative variables obtained from principal components analysis (SNA, SNB, and Björk sum), K-means cluster analysis was performed to classify the phenotypes. Statistical analysis was conducted to characterize the differences in the cephalometric variables among the clusters.ResultsClass III phenotypes were classified into nine clusters from the following four major groups: (1) retrusive maxilla group, clusters 7 and 9 (7.1% and 5.5%; severely retrusive maxilla, normal mandible, severe and moderate hyperdivergent, respectively) and cluster 6 (9.2%; retrusive maxilla, normal mandible, normodivergent); (2) relatively protrusive mandible group, cluster 2 (20.9%; normal maxilla, normal mandible, hyperdivergent); (3) protrusive mandible group, clusters 3 and 1 (11.7% and 15.3%; normal maxilla, protrusive mandible, normodivergent and hyperdivergent, respectively) and clusters 8 and 4 (15.3% and 3.7%; normal maxilla, severe protrusive mandible, normodivergent and hypodivergent, respectively); and (4) protrusive maxilla and protrusive mandible group, cluster 5 (11.4%; protrusive maxilla, severely protrusive mandible, normodivergent). Considerations for presurgical orthodontic treatment and OGS planning were proposed based on the Class III phenotypes.ConclusionsBecause the anteroposterior position of the maxilla and rotation of the mandible by a patient''s vertical pattern determine Class III phenotypes, these variables should be considered in diagnosis and treatment planning for patients who have skeletal Class III malocclusion.     

The effects of computer-aided anteroposterior maxillary incisor movement on ratings of facial attractiveness.

BACKGROUND: Before planning orthodontic treatment, it is necessary to understand societal preferences for facial esthetics. The anteroposterior (AP) position of the maxillary incisors affects the appearance of the soft tissue profile and can be manipulated by orthodontic techniques. To improve the ability to predict the most suitable maxillary incisor position, numerous cephalometric and profilometric measurements have been suggested. Among them are the Six Elements to Orofacial Harmony proposed by L. F. Andrews, whereby forehead angulation is used to dictate maxillary incisor sagittal position. Our aim was to evaluate differences in preference for the AP position of the maxillary incisor between orthodontic and lay panels. METHODS: A smiling profile photograph was taken of a female subject who best fit the chosen soft tissue normative values and whose maxillary incisors were in an Element II position. The photograph was manipulated to simulate maxillary protrusion and retrusion at 1-mm increments to a maximum of +/-4 mm. Panels of orthodontists and nonorthodontists scored the attractiveness of the photographic variations according to a 100-mm visual analogue scale. RESULTS: The 4-mm retrusive photograph was significantly less desirable than all others, which suggests that, from an esthetic standpoint, it is preferable to either leave a normally protrusive maxillary dentition where it is or advance rather than retract the maxillary anterior teeth. Orthodontic training did not significantly affect the magnitude of the ratings or pattern of preference in our sample. CONCLUSIONS: Andrews' Element II provides an additional useful method to evaluate attractiveness relative to the maxillary incisor position.     

双颌前突畸形正畸治疗后颅面硬组织变化的研究

目的研究正畸治疗对双领前突患者硬组织矢状及垂直向的影响。方法对24例广东籍双领前突患者在拔除4个第一双尖牙后,采用标准方丝弓矫治技术进行矫治,并对矫治前后硬组织侧貌的变化进行分析。结果 ①上下领骨间关系无明显变化,上下前牙突度和倾斜度明显减小。②前后面高明显增加,但前后面高间的比值及反映下领平面倾斜度的MP-FH无明显变化。③上下磨牙高度随前后面高的增加而明显增加。④上前牙高度明显增加,下前牙高度明显减小。结论双领前突畸形正畸治疗中垂直向及矢状向支抗可得到较好控制。     

Components of adult class III malocclusion

To identify the skeletal and dental relationships of adults who have class III malocclusion, lateral cephalograms of 302 adult patients who had a class III molar and cuspid relationship were traced. Ninety-four of the patients had had presurgical orthodontic treatment and 208 had not. The tracings were digitized, and the following sets of measures were analyzed: maxillary skeletal position; maxillary dentoalveolar position; mandibular dentoalveolar position; and mandibular skeletal position. In addition, the mandibular plane angle and lower anterior facial height were measured as an indicator of vertical facial dimensions. None of these values demonstrated significant gender differences except lower anterior facial height; therefore, the subjects were treated as a group. Although there was considerable variation among patients, the most common combination of variables was a retrusive maxilla, protrusive maxillary incisors, retrusive mandibular incisors, a protrusive mandible, and a long lower facial height.     

Ranking of Facial Profiles among Asians

The purpose of this study was to determine the facial profile preferences in a sample of 1,189 Asian teenagers (aged 15.3 ± 3.2 years). Five facial profile types were computer-generated by trained personnel (orthodontists and oral maxillofacial surgeons) to represent distinct facial types. Subjects were asked to rank the profiles in descending order of attractiveness. The ranking was as follows: orthognathic profile, bimaxillary retrusive profile, bimaxillary protrusive profile, mandibular retrognathic profile, and mandibular prognathic profile. The differences in rank scores between all the profile types were statistically significant (p < 0.05). Assessment of profile types among lay personnel could provide clinicians an indication into the relative attractiveness among profile types and health care workers in treatment prioritization among dysmorphic facial types.     

Ranking of facial profiles among Asians.

The purpose of this study was to determine the facial profile preferences in a sample of 1,189 Asian teenagers (aged 15.3 +/- 3.2 years). Five facial profile types were computer-generated by trained personnel (orthodontists and oral maxillofacial surgeons) to represent distinct facial types. Subjects were asked to rank the profiles in descending order of attractiveness. The ranking was as follows: orthognathic profile, bimaxillary retrusive profile, bimaxillary protrusive profile, mandibular retrognathic profile, and mandibular prognathic profile. The differences in rank scores between all the profile types were statistically significant (p < 0.05). Assessment of profile types among lay personnel could provide clinicians an indication into the relative attractiveness among profile types and health care workers in treatment prioritization among dysmorphic facial types.     

Outcome of orthognathic surgery in Chinese patients. A subjective and objective evaluation

OBJECTIVE: To evaluate the outcome of orthognathic surgery by objective cephalometric measurement of posttreatment soft-tissue profile and by subjective evaluation of profile esthetics by laypersons and clinicians. MATERIALS AND METHODS: The sample consisted of 30 Chinese patients who had completed combined orthodontic and orthognathic surgical treatment. The posttreatment cephalograms of these patients were analyzed with respect to profile convexity, facial height, and lip contours and these were compared to the previously established esthetic norms. Line drawings of the soft-tissue profile were displayed to a panel comprising six laypersons and six clinicians who scored the esthetics of each profile using a 7-point scale. RESULTS: Complete normalization of cephalometric soft-tissue variables was not achieved with orthognathic surgery in most patients, with four of the six soft-tissue cephalometric measurements showing significant differences compared to the esthetic norms. There were good correlations in the esthetic scores between laypersons and clinicians, even though clinicians tend to rate the profiles more favorably. Facial convexity and facial height did not significantly influence the subjective scores of both the laypersons and clinicians. Lower lip protrusion was the only cephalometric variable that significantly influenced clinicians' assessment of profile esthetics (P<.01). CONCLUSIONS: Profile convexity and lower facial height proportion had little influence on both lay and professional perception of profile esthetics. Lower lip position is the only cephalometric variable that significantly influenced clinicians' assessment of profile esthetics.     

骨性Ⅲ类错(牙合)正颌术后侧貌预测及评价

目的:预测骨性Ⅲ类错(牙合)患者双颌术后侧貌,经审美评分,确定侧貌美观度,为手术方案设计提供参考. 方法:选择重庆医科大学口腔医院正畸科骨性Ⅲ类错(牙合)患者1例,以 Photoshop CS4模拟患者术后侧貌,以Andrews美学理论二要素设计上颌硬组织前徙位置,以中国人软组织面型角设计下颌骨后退位置,预测出侧貌标准图P1.在P1上分别矢状向移动B’点及Pog’点±1、±2、±3、±5、±7 mm,获得20幅面型图,随机排列,由专业组、非专业组共128人评分;采用SPSS13.0软件包中的Wilcoxon秩和检验比较21幅预测图得分及2个评价组是否有差异.结果:21幅侧貌图得分具有显著差异(P＜0.05).被认为美观的侧貌得分由高至低:分别为图D3、D2、D1 、B1 、A1 、P1 、C1 、A2、B2;被认为不能接受的侧貌图依次为:图C5 、B5 、C4 、A5.专业组及非专业组的审美评分无显著差异(P＞0.05).结论:人们对侧貌美观度的认知不同,直面型最美观,其次是下颌或颏部稍后缩的面型,而下颌或颏部严重前突或后缩被认为是很不美观且不能为人接受.     

The frequency and distribution of skeletal and dental components in Class II orthognathic surgery patients

In an effort to identify the skeletal and dental relationships of Class II malocclusion, lateral cephalograms of 253 adult orthognathic surgery patients (76 male, 177 female) who had a Class II molar and cuspid relationship were traced. One hundred and four of the subjects had had presurgical orthodontic treatment and 148 had not. The most common combination of variables found in this study population was a retrusive maxilla, protrusive maxillary incisors, protrusive mandibular incisors, a retrusive mandible, and a long lower facial height.     

Forsus和Frnkel-Ⅱ治疗下颌后缩畸形的临床对比研究

目的:比较Forsus(F)和Frnkel-Ⅱ(FR-Ⅱ)2种功能矫治器对生长发育高峰期下颌后缩患者牙颌面结构的影响。方法:按纳入标准选取32例患者,随机分成F组与FR组,分别采用Forsus和Frnkel-Ⅱ进行治疗。以矫治前后的X线头影测量片评价其疗效,并进行对比。结果:2种功能性矫治器都能促进下颌骨生长,增加下颌骨长度;FR-Ⅱ对上颌骨有一定抑制作用,与F组相比差异有显著性(P<0.01);2种功能矫治器产生下前牙唇倾量以F组更多,2组间差异存在显著性。结论:Forsus、FR-Ⅱ对青春生长发育高峰患者都有明显的下颌骨矫形效果;Forsus矫治器适用于下颌发育不足、上颌发育正常且下前牙较为直立的Ⅱ类患者,Frnkel-Ⅱ则适用于伴有上下切牙牙轴较前倾、上颌正常或轻度前突的下颌后缩患者。     

Preferences for facial profiles between Mexican Americans and Caucasians

The objective of this study was to determine differences between Mexican American and Caucasian judges in the acceptability of lip protrusion in computer animations of two male and two female persons of Mexican descent. Thirty Caucasians and 30 Mexican Americans of varying age, sex, education, and level of acculturation responded to facial profile computer animations that moved lips from an extreme protrusive to an extreme retrusive position. Judges were asked to complete two tasks: (1) to press the mouse button when the image was perceived to be most pleasing (MP) and (2) to determine the boundaries of a zone of acceptability (ZA) of lip protrusion by pressing the mouse button when the moving image became acceptable and releasing it when the image of the protrusion became unacceptable. In general, Mexican Americans preferred upper or lower lip positions to be less protrusive than did Caucasians. Larger mean ZAs for both upper and lower lip positions with male computer animation images and lower lip position for female computer animation images were found among Caucasians when compared with low-acculturated Mexican Americans. A significant mean difference in midpoint of acceptability (MA) for lip position between Caucasians and low-acculturated Mexican Americans was observed for both upper and lower lip position with female computer animation images.