Comparison of Chinese and US orthodontists' averaged evaluations of "facial attractiveness" from end-of-treatment facial photographs

Reliability assessment and correlation analysis of evaluating orthodontic treatment outcome in Chinese patients

This study aimed to assess the reliability of experienced Chinese orthodontists in evaluating treatment outcome and to determine the correlations between three diagnostic information sources. Sixty-nine experienced Chinese orthodontic specialists each evaluated the outcome of orthodontic treatment of 108 Chinese patients. Three different information sources: study casts (SC), lateral cephalometric X-ray images (LX) and facial photographs (PH) were generated at the end of treatment for 108 patients selected randomly from six orthodontic treatment centers throughout China. Six different assessments of treatment outcome were made by each orthodontist using data from the three information sources separately and in combination. Each assessment included both ranking and grading for each patient. The rankings of each of the 69 judges for the 108 patients were correlated with the rankings of each of the other judges yielding 13 873 Spearman r_s values, ranging from –0.08 to +0.85. Of these, 90% were greater than 0.4, showing moderate-to-high consistency among the 69 orthodontists. In the combined evaluations, study casts were the most significant predictive component (R²=0.86, P<0.000 1), while the inclusion of lateral cephalometric films and facial photographs also contributed to a more comprehensive assessment (R²=0.96, P<0.000 1). Grading scores for SC+LX and SC+PH were highly significantly correlated with those for SC+LX+PH (r_{(SC+LX)vs.(SC+LX+PH)}=0.96, r_{(SC+PH)vs.(SC+LX+PH)}=0.97), showing that either SC+LX or SC+PH is an excellent substitute for all three combined assessment.

Evaluation of facial attractiveness for patients with malocclusion: a machine-learning technique employing Procrustes

OBJECTIVE

To establish an objective method for evaluating facial attractiveness from a set of orthodontic photographs.

MATERIALS AND METHODS

One hundred eight malocclusion patients randomly selected from six universities in China were randomly divided into nine groups, with each group containing an equal number of patients with Class I, II, and III malocclusions. Sixty-nine expert Chinese orthodontists ranked photographs of the patients (frontal, lateral, and frontal smiling photos) before and after orthodontic treatment from "most attractive" to "least attractive" in each group. A weighted mean ranking was then calculated for each patient, based on which a three-point scale was created. Procrustes superimposition was conducted on 101 landmarks identified on the photographs. A support vector regression (SVR) function was set up according to the coordinate values of identified landmarks of each photographic set and its corresponding grading. Its predictive ability was tested for each group in turn.

RESULTS

The average coincidence rate obtained for comparisons of the subjective ratings with the SVR evaluation was 71.8% according to 18 verification tests.

CONCLUSIONS

Geometric morphometrics combined with SVR may be a prospective method for objective comprehensive evaluation of facial attractiveness in the near future.

Clinicians and laypeople assessment of facial attractiveness in patients with cleft lip and palate treated with LeFort I surgery or late maxillary protraction

OBJECTIVE

To assess the changes in the facial attractiveness (FA) in two groups of cleft lip and palate patients with Class III malocclusions treated using LeFort I surgery or late maxillary protraction.

MATERIALS AND METHODS

Standardized pre- and post-treatment photographs were taken of 32 patients (17 corrected by orthognathic surgery and 17 by late maxillary protraction). The photographs were randomized and 42 clinicians and 121 laypeople rated them on a 10-point FA scale via a web-based survey.

RESULTS

Clinicians' mean FA values increased from 4.45 to 5.16 [95% CI of mean difference (MD), 0.59-0.82, p<0.001] in surgical cases and 4.84 to 5.30 (95% CI of MD, 0.35-0.56, p<0.001) in protraction cases. The laypeople mean FA values increased from 5.07 to 5.54 (95% CI of MD, 0.40-0.53, p<0.001) in surgical cases and 5.51 to 5.68 (95% CI of MD, 0.11-0.23, p<0.001) in protraction cases. When patients combined, laypeople rated FA 0.64 points higher (95% CI, 0.54-0.74, p<0.001) in pre-treatment and 0.38 points higher (95% CI, 0.27-0.48, p<0.05) in post-treatment relative to clinicians.

CONCLUSION

Both clinicians and laypeople perceived an improvement of FA after both treatments. Laypeople rated FA higher compared to clinicians.

Age, extraction rate and jaw surgery rate in Korean orthodontic clinics and small dental hospitals

Objective

This study aimed to investigate the current data regarding age, sex, and Angle Classification of Korean orthodontic patients and influence of these factors on the tendency to undergo extraction and orthognathic surgery.

Methods

The recent trends of Korean orthodontic patients were assessed using questionnaire survey. The questionnaires were e-mailed to orthodontists who met the study criteria; 58% of the orthodontists opened the e-mails, and 27.7% replied to the e-mails. In all, the medical records of 11,340 patients who underwent orthodontic treatment at private clinics and small dental hospitals in Korea were analyzed.

Results

The percentage of female patients in the study sample was 69.6%, and the average age of the patients was 19.87 years. The percentage of patients who were older than 19 years was 50.2%. Class II and Class III malocclusions were noted in 33.6% and 23.6% of patients, respectively. Extraction and orthognathic surgery were performed in 60.4% and 6.9% of patients, respectively.

Conclusions

The results showed that there were a high percentage of adult, Class II malocclusion and extraction patients in private practices and small dental hospitals during the study period. Further, a relatively high proportion of adult patients opted to undergo orthognathic surgery.

Patients' self-perception of dentofacial attractiveness before and after exposure to facial photographs

OBJECTIVE

To determine whether exposure to pretreatment photographs of themselves influenced patients' self-perception of dentofacial attractiveness and willingness to undergo treatment.

MATERIALS AND METHODS

A total of 100 subjects of white ancestry aged 18 years or older (Study Group) and 100 sex- and age-matched controls (Control Group) were selected. Photographs of the frontal view of the face and the profile view of the face, both at rest and while smiling, were taken of each participant. Only Study Group subjects were given a printed copy of their own images to be examined at home between the initial observation (T0) and a set date an average of 30 days later (T1). Each of the 200 subjects in the study completed a questionnaire at T0 and T1 exploring happiness regarding their smiles and their facial profiles, as well as willingness to undergo treatment.

RESULTS

At T1 in the Study Group, 50% of subjects responded with a lower opinion of their facial profiles than at T0; 11% and 45% were willing to undergo more comprehensive procedures to change the appearance of their smiles and profiles, respectively. No statistically significant change was seen in questionnaire answers between T0 and T1 for the Control Group.

CONCLUSION

Laypeople generally are not aware of their facial profiles. Pretreatment photograph exposure can increase profile self-awareness, an important factor in reducing the discrepancy between orthodontists' and patients' visual emphasis on dentofacial esthetics.

Correlations between cephalometric and photographic measurements of facial attractiveness in Chinese and US patients after orthodontic treatment

INTRODUCTION

Orthodontists rely on esthetic judgments from facial photographs. Concordance between estimates of facial attractiveness made from lateral cephalograms and those made from clinical photographs has not been determined. We conducted a preliminary examination to correlate clinicians' rankings of facial attractiveness from standardized end-of-treatment facial photographs (Photo Attractiveness Rank) with cephalometric measurements of facial attractiveness made for the same subjects at the same time.

METHODS

Forty-five Chinese and US orthodontic clinicians ranked end-of-treatment photographs of separate samples of 45 US and 48 Chinese adolescent patients for facial attractiveness. Separately for each sample, the photographic rankings were correlated with the values of 21 conventional hard- and soft-tissue measures from lateral cephalograms taken at the same visits as the photographs.

RESULTS

Among US patients, higher rank for facial attractiveness on the photographs was strongly associated with higher values for profile angle, chin prominence, lower lip prominence, and Z-angle, and also with lower values for angle of convexity, H-angle, and ANB. Among Chinese patients, higher rank for facial attractiveness on the photographs was strongly associated with higher values for Z-angle and chin prominence, and also with lower values for angle of convexity, H-angle, B-line to upper lip, and mandibular plane angle. Chinese patients whose %lower face height values approximated the ethnic "ideal" (54%) tended to rank higher for facial attractiveness than patients with either higher or lower values for %lower face height. The absolute values of the correlations for the 7 US measures noted above ranged from 0.41 to 0.59; those of the 7 Chinese measures ranged from 0.39 to 0.49.The P value of the least statistically significant of these 14 correlations was 0.006, unadjusted for multiple comparisons. On the other hand, many cephalometric measures believed by clinicians to be indicators of facial attractiveness failed to correlate with facial attractiveness rank for either ethnicity at even the P <0.05 level, including SN-pogonion angle, lower incisor to mandibular plane angle, and Wits appraisal.

CONCLUSIONS

In general, there was less association than expected or desired between objective measurements on the lateral cephalograms and clinicians' rankings of facial attractiveness on sets of clinical photographs.