Perceptions of Altered Smile Esthetics: A Comparative Evaluation in Orthodontists, Dentists, and Laypersons

Virtual sketching-based dental anatomy module improves learners' abilities to use computer-aided design to create dental restorations and prostheses

Dental anatomy education for dental technology students should be developed in alignment with digital dental laboratory practices. We hypothesized that a virtually assisted sketching-based dental anatomy teaching module could improve students' acquisition of skills essential for digital restoration design. The second-year dental technology curriculum included a novel virtual technology-assisted sketching-based module for dental anatomy education. Pre- and post-course assessments evaluated students' skill sets and knowledge bases. Computer-aided design (CAD) scores were analyzed after one year to assess how the skills students developed through this module impacted their subsequent CAD performance. Participants who undertook the dental sketching-based teaching module demonstrated significantly improved theoretical knowledge of dental anatomy, dental aesthetic perception, and spatial reasoning skills. A partial least squares structural equation model indicated that the positive effects of this module on subsequent CAD performance were indirectly mediated by dental aesthetic perception, spatial reasoning, and practice time. A virtually assisted sketching-based dental anatomy teaching module significantly improved students' acquisition of skills and knowledge and positively mediated dental technology students' CAD performance.

Association of LSMx and LIMd Angles With Cephalometric Dental and Soft Tissue Parameters of Incisor Proclination and Lip Protrusion

BACKGROUND

Soft tissue analysis can be used to assess anatomical features but may or may not accurately correlate with underlying hard tissue morphology, leading to an incorrect perception of malocclusion.

OBJECTIVE

This study aimed to assess the reliability of different soft tissue reference lines used to evaluate anteroposterior lip position and the position of incisors and malocclusion and compare it with those assessed via hard tissue angles (LSMx and LIMd) and determine if they are true indicators of underlying protrusion of incisors and malocclusion.

METHOD

A total of 120 pre-treatment lateral cephalometric radiographs were selected where patients were 18-30 years old, diagnosed as Skeletal Class I, II (Division 1 and 2), and III malocclusion. The measurements taken were SN to point A angle (SNA), SN to point B angle (SNB), angle between point A and point B (ANB), upper incisor to SN plane angle (UI-SN), upper incisor to palatal plane angle (UI-PP), incisor mandibular plane angle (IMPA), Ricketts' E line, Sushner's S2 line, nasolabial (NL) angle, mentolabial (ML) angle, LSMx angle, and LIMd angle.

RESULTS

In the Class I malocclusion group, when the upper lip was assessed, the distribution of UI-SN, UI-PP, E line to UL, S line to UL, NL angle, and LMax was significantly different statistically (p=0.000), though the assessment of lower variables in Class I malocclusion showed the distribution of IMPA, E line to UL, S line to UL, ML angle, and LMand angle has a statistically significant difference (p=0.007). In Class II Division 2 malocclusion, a significant difference was observed for the upper variables (p=0.000), whereas the distribution of lower values was the same across all the variables (p=0.0724). In the sample of Class III malocclusion, a significant correlation was found in the upper variables, while the distribution among lower variables did not show any significant difference (p=0.211).

CONCLUSION

This study indicates that the upper and lower soft tissue correlation with hard tissue variables is reliable for some variables but not throughout for all. Soft tissue analysis (under study) can be used to assess disproportion, but it fails to correlate to the underlying hard tissue morphology and does not explain the correct malocclusion. Further studies based on 3D diagnosis to formulate a close relationship are encouraged that can help assess soft and hard tissue patterns consistent with one another.

Aesthetic assessment of maxillary lateral and canine implant-supported crowns by laypersons and orthodontists

INTRODUCTION

The objectives of this study were to evaluate how laypersons and orthodontists evaluate and rank aesthetic parameters of an implant-supported crown (ISC) on the canine position (ISC-C) and lateral position (ISC-L).

METHODS

A digital survey of 11 cases, 5 ISC-C, 5 ISC-L and 1 control case without ISC, was distributed to 207 laypersons and 296 orthodontists. All cases included one extraoral photograph and three intraoral photographs. The respondents were asked to identify the ISC and to evaluate the aesthetic parameters regarding colour of the implant (CI), shape of the implant (SI) and gingival colour around ISC (GCI). Differences within and between the groups were tested using Chi-2-test and Independent-Samples t-test.

RESULTS

All invited laypersons and 184 orthodontists (62% response rate) answered the survey. Orthodontists (89%) more correctly identified the ISC, regardless of its position, than laypersons (50%) (p < 0.001). Both laypersons (54%) and orthodontists (23%) rated higher proportions of acceptance of CI, SI and GCI in favour for the ISC-L than ISC-C (laypersons: 40%, orthodontists: 10%) (p < 0.001). Assessing each parameter separately, orthodontists rated higher for ISC-L, compared to the ISC-C (p < 0.001). In general, laypersons and orthodontist ranked tooth colour (mean, standard deviation [SD]:8.0,1.5 and 9.0, 1.0) and tooth shape (mean, SD: 8.0, 1.7 and 8.8, 1.2) as aesthetically higher than the gingival colour (mean, SD: 7.2, 2.2 and 8.0, 1.7) (p > 0.001).  Conclusion: Laypersons and orthodontists consider the ISC-L as aesthetically more preferable, compared to the ISC-C.

Layperson assessment of smile lines and upper lip combined images in smile esthetics

STATEMENT OF PROBLEM

The esthetic assessment of smile lines by laypersons is a subject of ongoing debate. However, smile lines often appear with different types of upper lip curvature, which further complicates the esthetic assessment process, and studies on this combination are lacking.

PURPOSE

The purpose of this clinical study was to investigate a layperson's esthetic perception of smile lines and upper lip combined images.

MATERIAL AND METHODS

Twenty-six smile images resulting from combinations of 3 upper lip types, 4 anterior smile line types, and 3 posterior smile line types were generated by an image editing software program. Eighty-three laypersons (39 men and 44 women; 18 to 35 years of age) completed rating images using a visual analog scale. Unattractive smiles were designated to be those with scores <50 and attractive ones with scores ≥50. Data were analyzed using 1-way analysis of variance and Bonferroni post hoc tests (α=.05).

RESULTS

High anterior smile line with gingival display >4 mm obtained significantly lower scores of <50 when combined with all upper lip curvatures (upward: 28.29 ±22.79, straight: 38.74 ±23.00, downward: 30.67 ±22.25, P<.01). High anterior smile lines with gingival display ≤4 mm combined with upward and straight upper lip curvature images obtained significantly higher scores, and all were ≥50 (upward: 63.24 ±22.22, straight: 61.40 ±21.58, P<.01).

CONCLUSIONS

From a layperson's perspective, high anterior smile lines with gingival display >4 mm combined with any lip type were determined to be unattractive. If gingival display was ≤4 mm combined with both upward and straight lip types, the smile was assessed as attractive.

Customized planning of the visible maxillary arch width in harmony with interparopia width and smile width for female facial aesthetics

BACKGROUND

The visible maxillary arch width (VAW) is an important aesthetic-determining feature. To date, there is no well-established methodology to determine the aesthetically optimal VAW in customized treatment planning.

METHODS

In this study, the common traits of the dentofacial configuration were investigated in most attractive Asian and Caucasian female smiles. The smiling photo of a subject was digitally modified based on combined variations of VAW, smile width (SW), transverse facial dimensions (TFD), and vertical facial dimensions. These modified photos were assessed for aesthetics. The aesthetically essential parameters were identified, and their mathematic correlations and reference ranges were determined for different vertical facial patterns. Using the obtained results, a mathematic guidance was constructed for customized smile designing. The applicability of this guidance was tested in Asian females.

RESULTS

The most attractive Asian and Caucasian female smiles have intraracial and interracial commonalities in the VAW-to-TFD ratios. The interparopia width (IPD) predominated over facial widths in determining well-matched VAW and SW. For optimal smile aesthetics, the VAW and SW were correlated as simulated by the formula 1.92 IPD ≤ VAW + 2.3 SW ≤ 2.17 IPD, plus the VAW-to-IPD ratio within 0.54 to 0.62 and the SW-to-IPD ratio within 0.61 to 0.71, ranges tailored to vertical facial patterns. This constitutes a mathematic guidance for customized planning of the aesthetically optimal VAW. This guidance was preliminarily validated to be applicable to Asian females.

CONCLUSIONS

The VAW-to-TFD ratios were essential for Caucasian and Asian female smile aesthetics. The mathematic guidance could serve as a reference for customized smile designs for Asian females.

Laypersons' Esthetic Perception of Different Dentogingival Characteristics Based on Smile Dynamics: Cross-Sectional Study

This study aimed to evaluate laypersons' esthetic perception of different dentogingival characteristics based on smile dynamics. Six voluntary models were selected, with only one presenting dentogingival characteristics within esthetic standards: white teeth, good alignment, and adequate gingival contour. Two videos were then produced. One video focused on the mouth, whereas the other focused on the entire face of the model, to ensure that the dynamics of the smile could be evaluated. For the evaluation, 200 laypeople were asked to rank the models from first to sixth place in their order of preference. Laypeople were required to justify their reasons for choosing the first and last places. The obtained data were subjected to descriptive and inferential statistical analyses. The results showed that smile and face dynamics influenced the perception of dentogingival characteristics and facial esthetics. No significant changes were observed. However, a gummy smile accompanied by dental alterations was observed in the video of the mouth and was masked by the facial set exposed in the video of the face. A diastema between the central incisors was decisive for negative evaluation of both the mouth and face. The standard model was rated as the most pleasing. Smiles and facial dynamics influence the perception of dentogingival characteristics. Smile and facial dynamics influence the perception of dentogingival alterations among Brazilian laypeople. Diastema is an alteration that interferes with the isolated evaluation of the lower third of the face and the facial set.

Evaluating smile aesthetic satisfaction and related smile characteristics in dental students

Aim

This study aimed to assess the association between self-rated smile satisfaction and the smile dimensions among dental students.

Method

An analytical cross-sectional study was conducted on 216 Vietnamese dental students. A standardized photograph was taken of each student with their frontal social smiles to assess aesthetic dimensions. A single-session self-administered questionnaire containing five questions about smile aesthetic satisfaction related to various aspects was administered to all students. Differences in smile characteristics and satisfaction scores between the two genders were evaluated. The impact of smile characteristics on satisfaction scores was assessed using multiple linear regression models.

Results

Most dental students had a high smile line, parallel smile arcs, an upward upper lip curvature, a non-touching labiodental relationship, a dental midline that coincided with the midline of the face, and eight teeth displayed during smile. Most participants were satisfied with their smiles, and the self-rated satisfaction score was 67 out of 100. Self-perceived overall smile satisfaction was associated with the "smile arc", the "upper lip curvature", the "number of teeth displayed during smile", and the "dental midline". Female students had a statistically significant correlation between self-perception and smile characteristics, such as upper lip curvature, dental midline shift, and smile line.

Conclusions

The smile arc, upper lip curvature, and dental midline shift affected self-perceived satisfaction among dental students. Female students showed an association between the smile parameters and self-perceived satisfaction.

Smile Aesthetics Assessment in Patients Undergoing the Finishing Phase of Orthodontic Treatment: An Observational Cross-Sectional Study

Objective To describe the smile characteristics of patients entering the finishing phase of orthodontic treatment. Methods This observational study involved a non-probabilistic sample of 48 patients. Clinical records served as the basis for determining the type of treatment (with or without extractions). Photographs were analyzed to obtain smile variables. Dental casts and panoramic radiographs were evaluated to ascertain the cast-radiograph evaluation (CRE) index. Univariate and bivariate analyses were conducted at a significance level of 0.05. Results The study evaluated 24 men and 24 women, with an average age of 20.10 ± 6.78 years. Fifty percent of the patients did not undergo extractions, and the average CRE index for the sample was 34.83 ± 9.01. Regarding the smile, a medium smile line was prevalent in 66.7% of cases, and a non-consonant smile arc was observed in 58.3%. Significant differences in the smile arc were found between patients with and without extractions (p=0.019). Right and left buccal corridors measured 2.52 mm ± 1.52 and 2.43 mm ± 1.37, respectively. The upper dental midline deviated by 0.80 ± 0.91 mm and had an angulation of 1.65 ± 2.05º. Both variables showed significant differences between Class I and Class II patients (p=0.020; p=0.027). Symmetrical smiles were also observed (1.05 ± 0.17). Conclusions Based on our findings, clinicians should focus on the smile arc in patients who have not undergone extractions and on the midline inclination in Class II patients. These appear to be the most common areas for improvement in patients who are in the finishing phase of treatment. Additionally, considerable variability exists in the smile characteristics of patients still undergoing orthodontic treatment, leaving room for further enhancement of results.

Does different vertical position of maxillary central incisors in women with different facial vertical height affect smile esthetics perception?

BACKGROUND

The aim of this study was to assess the esthetic perceptions of orthodontists, prosthodontists and laypersons with regard to different vertical positions of the maxillary central incisors related to lateral incisors for different facial vertical height cases.

SUBJECT AND METHODS

Frontal full-face photographs showing social smiles of three adult women aged between 18 and 25 years were used. Vertical position of the maxillary central incisor was changed (intruded or extruded) with 0.5 mm increments according to the reference gingival line resulting five images for each woman in a full-face view yielding a total of 15 images. A visual analog scale was placed below each smile to allow the raters to evaluate the attractiveness of each smile independently. One-way analysis of variance was used to determine whether there was a difference between more than two independent groups in terms of quantitative variables. Comparisons of more than two dependent groups were examined with repeated measures one-way ANOVA. The significance level was taken as 0.05 for all analyses.

RESULTS

For increased facial vertical height, the highest scores for orthodontists were given to the 0.5 mm extruded (64.18 ± 26.36), for prosthodontists to the control (57.28 ± 19.80), and for layperson to the 1 mm extruded (61.27 ± 25.98) central incisor position. For decreased facial vertical height, the highest scores were obtained at the 0.5 mm intrusion with an increasing pattern from orthodontists to laypersons (63.95 ± 22.08 for orthodontists, 79.87 ± 21.43 for prosthodontists, and 79.88 ± 19.17 for laypersons). All three rater groups gave the highest scores to the 0 mm (control) smile design for normal facial vertical height. When these scores were compared among the groups, laypersons gave significantly higher scores compared to orthodontists (p < 0.001) and prosthodontists (p = 0.005).

CONCLUSIONS

The facial vertical height significantly affected the perception of smile esthetics. Keeping the distance between the central and lateral incisors longer than 1 mm in individuals with increased facial height may be important in terms of increasing patient satisfaction in terms of clinical aesthetics. On the contrary, keeping the distance between the central and lateral incisors shorter than 1 mm may create a more esthetically acceptable result in individuals with short facial height.

Optimal gingival display on smiling based on different facial vertical patterns in Iranians

INTRODUCTION

This study aimed to determine the optimal gingival display on smiling on the basis of different facial vertical patterns in Iranians from the perspective of laypeople, maxillofacial surgeons, and orthodontists.

METHODS

Photographs were obtained from short-faced, normal-faced, and long-faced males and females (1 male and 1 female from each group) aged 18-30 years. The original photographs were then modified to have 6, 4, 2, 0, -2, -4, and -6 mm gingival display. Three groups of raters (n = 40), including laypeople, orthodontists, and maxillofacial surgeons, were requested to score each photograph regarding smile attractiveness using a 5-point Likert scale. Data were analyzed using analysis of variance and the Kruskal-Wallis test.

RESULTS

Regarding the photographs of the normal-faced female model, all 3 rater groups gave the highest score to a 2 gingival display. In the normal-faced male model, all 3 rater groups gave the highest and lowest scores to 0 and 6 mm gingival display, respectively. In the long-faced female model, all 3 rater groups gave the same score to 0, 4, and 6 gingival display. In the long-faced male model, the 3 rater groups gave the same score to 0, 2, 4, and 6 gingival display. In the short-faced female model, all 3 rater groups gave the highest score to 0 gingival display. In the short-faced male model, the 3 rater groups gave the same score to all values of gingival display except -4 mm.

CONCLUSIONS

The laypeople, maxillofacial surgeons, and orthodontists all gave the highest score to the photograph of a short-faced Iranian female model with 0 gingival display.

Maxillary Midline Diastemas in West African Smiles

The maxillary midline diastema (MMD) has experienced a renaissance in popular culture over the last 10 years. Current literature states that MMDs should be eliminated where possible or be reduced to 1 mm or less in width. This literature review explores the evidence for this in a West African population. A systematic search of the literature (Medline and Google Scholar) followed by a hand search was carried out to identify all papers evaluating perceptions of MMDs. In all, 209 papers were identified in the literature search, 8 of which met the inclusion criteria. The review revealed that midline diastemas are desirable in this specific population with a width of 2 to 4 mm deemed as attractive. As many as 95% of participants found the MMD beautiful, and as many as 95% would consider having one created artificially. The literature does not support the position that MMDs larger than 1 mm should always be treated to be perceived as attractive in this population. MMDs are accepted as attractive and should be considered a key feature in smile design for this population.

Effect of variations in facial flow curves on the perceptions of smile esthetics by laypeople

STATEMENT OF PROBLEM

Information about the effect of the facial flow concept on the smile esthetic perception of laypeople is lacking.

PURPOSE

The purpose of this study was to determine the effect of the facial flow concept on laypeople's perception of smile esthetics.

MATERIAL AND METHODS

Frontal full-face images of a female volunteer were digitally altered to create commissural line and transverse occlusal plane inclinations, a dental midline shift, and facial asymmetries. A questionnaire was developed, and a single researcher asked 400 evaluators to rate the attractiveness of the different smiles by using a visual analog scale. The subsequent data were analyzed by using 3-factor repeated measures ANOVA and post hoc Bonferroni tests.

RESULTS

Images with commissural line and transverse occlusal plane inclinations pointing toward the green side of the facial flow curve were found to be more attractive than those with inclinations pointing to the red side (P<.001). Asymmetric facial images with the dental midline coinciding with the facial flow curve had higher esthetic scores than those without (P<.001). Images that showed parallelism between the transverse occlusal plane and commissural line inclinations were perceived as more esthetic (P<.001).

CONCLUSIONS

In an asymmetric face model, the degree and direction of commissural line and transverse occlusal plane inclinations and dental midline shift influenced the perceived attractiveness of a smile.

Aesthetic perception of smile in long face pattern patients who underwent maxillary impaction with miniplates or orthognathic surgery

INTRODUCTION

The gummy smile is perceived in 10% of the population aged 20 to 30 years old, and it causes an aesthetic imbalance in the smile. This study investigated the existence of differences in the aesthetic perception of the smile after correcting the gummy smile using two different techniques: orthognathic surgery for maxillary impaction and miniplate-aided orthodontic impaction.

METHODS

Photographs of 16 Long Face Pattern female patients were evaluated by 56 oral and maxillofacial surgeons, 56 orthodontists, and 56 laypeople before and after the treatment with one of the two techniques. These photographs were standardized using the Photoshop program, randomly organized, and then presented to the evaluators via the Google Meeting® application in the PowerPoint® program. To evaluate the attractiveness of the smile, the Visual Analogue Scale (VAS) was used. To analyze the intra and inter-examiner concordances, Spearman's correlation and Kendall's concordance tests were used, respectively. For intergroup comparison, the Friedman test was used, with a 5% significance level.

RESULTS

For all three groups of evaluators, the post-treatment evaluation results were superior to the results before the treatment: surgeons and orthodontists assigned higher scores for surgical cases and laypeople for orthodontic cases.

CONCLUSION

From a clinical point of view, there was no difference between the results of both techniques with regard to the aesthetic perception of smiles. A gingival exposure ranging from zero to two millimeters was considered the most aesthetic for all evaluators.

Influence of Dental Education on Esthetics Self-Perception and Shade Selection

A discrepancy is encountered between the esthetic self-perception and the actual need for treatment. The aim was to determine the influence of dental education on the patients' attitude, esthetic self-perceptions, and shade selection. This cross-sectional study asked participants to select the perceived shade of their incisors using a shade guide, and to complete a self-administered questionnaire assessing their attitude regarding teeth shade. The color coordinates (L*, a*, and b*) of their actual shades were recorded clinically, using a digital spectrophotometer. A Pearson correlation assessed the relation between the perceived and actual color coordinates. A linear regression assessed the association between the attitude towards the esthetic self-perception, background factors, and actual shades. A clinical shade selection was done digitally for 536 participants, comprising 40.1% preclinical dental students, 37.3% clinical dental students, and 22.6% non-dental participants. The perceived and actual a* and b* values were significantly correlated in the preclinical students, and L* and b* were correlated in the clinical students. Those who had not received any dental education showed better attitude scores than the clinical students. The color-matching skills were improved by education; therefore, this emphasizes the importance of teaching color selection in dental schools. Dental esthetic self-perception is also improved by increasing knowledge and skills through exposure to a variety of comprehensive dental cases.

Comparison between orthodontist, general dentist, and layperson in the perception of pink esthetics on smile: A cross-sectional study

Objectives:

Smile designing has become an essential part of dental training and a beautiful smile not only adds to the esthetics of the face but also conveys emotions and augments the self-esteem of an individual. A beautiful smile is achieved by well-balanced pink and white esthetics. This study was designed to evaluate the difference in perceptions of orthodontists, general dentists, and laypersons to alterations in gingival characteristics on smile.

Material and Methods:

Smile images were modified intentionally to obtain the desired variations in gingival features such as color and contour of free gingival margins, inflammation, pigmentation, gingival margins with or without recession, zenith, and interdental papilla. A total of 51 images were rated by orthodontists, general dentists, and laypersons using Q sort methodology.

Results:

Variations in the position of free gingival margin with recession was most negatively ranked gingival factor by orthodontists, general dentists, and laypersons followed by variations in the position of interdental papilla. Position of free gingival margin without a recession, color changes due to pigmentation, and inflammation were moderately ranked. Control images and altered gingival zenith images were most positively ranked. Bilateral changes were perceived more readily compared to unilateral in factors such as a black triangle, zenith position, pigmentation, inflammation, and recession.

Conclusion:

Orthodontists seem to be less tolerant in their evaluations in comparison to general dentists and laypersons. The findings of this study point toward a crucial fact that smile designing should focus on parameters that are perceived readily by the public in general.

A Cross-Sectional Online Survey on Knowledge, Awareness, and Perceptions of Hollywood Smile Among the Saudi Arabia Population

Background:

Hollywood smile has gained popularity in recent times to improve aesthetics among the general population. Since patients’ perceptions of dental aesthetics play a vital role in planning and evaluating cosmetic dental treatment, it is essential to understand their knowledge, awareness, and factors that influence their perceptions of dental aesthetics.

Objectives:

The objective of this study was to assess the knowledge, awareness, and perceptions of Hollywood smile among the general population in Saudi Arabia.

Methods:

A close-ended questionnaire consisting of demographic information and 20 questions related to Hollywood smile was circulated through social media in Saudi Arabia. Statistical analyses of the data obtained were performed using Statistical Package for Social Sciences software (SPSS version 17, USA). Frequencies, percentages, and mean and standard deviation were calculated using descriptive statistics. Pearson chi-squared test was employed to test the association between the demographic variables, such as age, gender, and education levels, with the questionnaire items.

Results:

A total of 4104 participants responded to the study questionnaire. The responses to the questionnaire revealed that nearly half of the participants were not satisfied with their dental appearance (48.6%). The majority of the participants had heard or known about Hollywood smile (98%). About 42% of study participants were aware of the complications involved in the procedure. The results revealed that the younger generation (18 to 30 years) had more awareness and felt more need for dental aesthetics (p=0.001). The proportion of male participants who underwent Hollywood smile correction were more than females (p=0.001). Graduates showed more awareness regarding smile, dental aesthetics, and Hollywood smile than the other categories (p=0.001).

Conclusion:

This study has shown that the younger generation, female participants, and graduates had more awareness regarding smile, dental aesthetics, and Hollywood smile.

Esthetic Evaluation and Acceptability of Different Hole Designs on Implant Crowns from the Perspective of Patients and Dentists in China

PURPOSE

Abutment access hole on dental implant crowns may facilitate crown retrieval and reduce cement overflow but present esthetic obstacle for patients. This study aimed to investigate the esthetic evaluation and acceptability of implant crowns with different hole designs from the perspective of patients and dentists.

MATERIALS AND METHODS

Anterior and posterior implant zirconia crowns were fabricated into three types: no hole (NH), 1 mm micro hole (MH), and 2.5 mm regular hole (RH). The NH crown was set as the control, and the anterior and posterior crowns with MH and RH were evaluated. The subjects, who were recruited randomly, were comprised of lay patients (n=60) and professional dentists (n=30). All subjects were invited to evaluate the esthetic performance of MH and RH crowns on a Visual Analog Scale (VAS), rate them from 0 to 10, state their acceptability of these crowns, and label them as acceptable and unacceptable.

RESULTS

The ANOVA analysis of the VAS esthetic evaluation showed that the size of the hole, the position of the teeth, and the professional background of the subject significantly and independently affected esthetic perception. Crowns with MH in the posterior position had higher esthetic scores and acceptability compared with crowns with RH in the anterior position, and dentists tended to show higher acceptance and better esthetic rating for crowns with holes compared with lay patients.

CONCLUSION

The hypothesis that patients and dentists hold similar esthetic evaluations or acceptability towards implant crown hole designs was rejected. Lay patients had a lower tolerance for venting holes than dentists. Crowns with 1 mm micro holes were more recommendable than crowns with regular abutment access holes from the point of view of satisfying patients' esthetic needs.

Smile Attractiveness Evaluation of Patients Selected for a U.S.-Based Board Certification Examination

Objectives The aims of this study were to assess smile attractiveness of a collection of 68 smiling photographs of successfully treated cases submitted to the American Board of Orthodontics (ABO) clinical examination and identify variables that influence the assessment.

Materials and Methods A panel of 81 non-Caucasian assessors from various clinical disciplines were instructed to score the smile attractiveness on a visual analog scale from 1 (least attractive) to 10 (most attractive) and to select which components contributed to a lesser attractive smile. The mean, standard deviations (SDs), and quartiles of the smile attractiveness were obtained with descriptive statistics. Multilinear regression analysis was performed to investigate the scores of the perceived quality of smile attractiveness when the clinical disciplines and gender of the assessors were the factors taken into consideration. Receiver operating characteristic (ROC) curve was generated to establish the relationship between smile attractiveness and the achievement of a perfect smile.

Results The mean (SD) rating of each clinical photograph of the anterior occlusion on smiling ranged from 3.11 (1.47) as the least attractive smile to 7.59 (1.45) as the most attractive smile. The overall mean (SD) score for smile attractiveness was 5.30 (1.10). Problems associated with teeth, gingiva, and lips corresponded with a reduction of the smile attractiveness score by 1.56, 1.82, and 1.47, respectively. Gender was not associated with smile attractiveness ratings. Orthodontists, periodontists, and prosthodontists demonstrated no difference in the ratings, while plastic surgeons were more critical than orthodontists regarding smile attractiveness.

Conclusions This study suggested that only 2 out of 68 AOB validated treatment finishes had a perfect and attractive smile.

Esthetic Smile Perception Among Dental Students at Different Educational Levels

Purpose

To evaluate the perception of six esthetic components of the smile among dental students and whether such a perception was influenced by different education levels and gender.

Materials and Methods

This was an analytical cross-sectional study. A self-administered questionnaire was applied to all students (n=182) at clinical levels (year four and five) to evaluate a total of 6 ideal images (smile arc [SA], buccal corridor [BC], gingival display [GD], midline diastema [MD], crown length [CL] and width [CW]). In addition, students were asked to evaluate 20 altered images of these ideal images. A 10-point visual analogue scale was used to assess the ideal images, with the right end of the scale labeled “attractive smile” and represented by the number 10 and the left end of the scale labeled “unattractive smile” and represented by the number 0. The opposite scoring was applied for the altered esthetics smile images. Descriptive statistics was run to report sample characteristics, and the Mann-Whitney U-tests were performed to compare clinical levels and gender on aspects of esthetic smile.

Results

The response rate was 80% (77 females and 68 males). Students at level five scored statistically significantly (p<0.001) higher towered attractive esthetic smile in ideal SA, while students at level four scored statistically significantly (p=0.016 and 0.006, respectively) higher towered attractive esthetic smile in ideal GD and CL. At altered smile esthetics images evaluation, fifth year dental students scored statistically significantly (p=0.030, 0.026 and 0.028, respectively) higher towered unattractive esthetic smile in two altered images of SA and one of BC. In contrast, fourth year dental students scored statistically significantly (p=0.022, 0.048, 0.027, respectively) higher towered unattractive esthetic smile in one altered image of GD, midline diastema and crown width. Males in year four were more likely to score higher than females for ideal images meanwhile females in year five scored higher than males towards attractive smile in ideal images. Males and females differences in scoring ideal images on both levels were generally non-significant (P>0.05) although males were statistically significantly to score higher than females towards unattractive images in both levels (p<0.05).

Conclusion

Dental students at the fifth-year level of study had higher perception of esthetic components of smile than those at the fourth-year level. At each level of study, female dental students apparently had higher perceptions of smile esthetics than males.

Influence of upper lip curvature on smile attractiveness in patients with different degrees of gingival smiles: A cross-sectional study with opinions from oral health providers and laypersons

INTRODUCTION

Although there is relative consensus about approaches to gingival smile management, there are still discrepancies as to whether a gingival smile is attractive or not. The purpose of this study was to quantify the influence of upper lip curvature shape and the amount of gingival display on the perception of smile attractiveness assessed by Peruvian orthodontists, dentists, and laypersons.

METHODS

A frontal photograph was digitally altered to generate 3 types of upper lip curvature shapes (upward, straight, and downward) with 5 different levels of gingival smile exposure (0 mm, 2 mm, 3 mm, 4 mm, and 5 mm). Fifteen images were generated. Three groups of evaluators (50 dentists, 50 orthodontists, and 50 laypersons) assessed the images using a visual analog scale. One-way analysis of variance with Bonferroni post-hoc tests and multiple linear regressions were applied.

RESULTS

The downward lip curvature shape had a negative effect on the esthetic evaluation of the smile with gingival exposures of 3 mm or more for all the evaluating groups (approximately 20-30 points less than upward or straight smile curvature shapes, P <0.05). Laypeople gave higher scores of almost 10 points more than dentists and orthodontists when evaluating the upward lip curvature shape with 5 mm of gingival exposure during smile (P = 0.029).

CONCLUSIONS

We found that upward or straight upper lip curvature shapes have a positive impact on perceived smile esthetics. In contrast, downward upper lip curvature shapes have a negative effect on perception when evaluating different degrees of gingival smiles.

Perception and Characterization of Posed Smile: A Photographic Study

Aims of the Study:

The aims of the study are: (a) to compare the perceptions of dental specialists and laypeople regarding smile esthetics; (b) to compare male and female smile parameters; (c) to find influence of smile parameters on esthetics of smile.

Materials and Methods:

The study was conducted on 60 subjects (30 males and 30 females) of age 18 to 25 years. Frontal posed photographs of all subjects were taken using a digital camera and rated on a visual analog scale by 10 dental specialists and 10 laypersons. Measurements made on photographs were used to analyze various parameters of smile, such as buccal corridor space, smile arc, modified smile index, anterior height of smile, most posterior maxillary tooth visible, and midline relationship of central incisors to philtrum.

Results:

Visual analog scale values showed that 6 photographs were rated as very good (3 males, 3 females), 29 as good (11 males, 18 females), 21 as average (13 males, 8 females), and 4 photographs were rated as bad (3 males, 1 female). A high correlation was observed between ratings of dental specialists and layperson’s ratings for both male and female smiles. Most of the subjects had non-consonant smile arc, and a high correlation was found between buccal corridor space on right and left sides in both males and females. Most of the male and female smiles had an average anterior height of smile; permanent maxillary first molar was the last tooth visible during smile (73.3% females, 66.7 males); and 55% subjects had coincident midline relationship of central incisors to philtrum.

Conclusion:

There was no significant difference in perception of dental specialists and laypersons regarding esthetics of smile. Smile arc and anterior height of smile influenced the esthetics of smile. No significant difference was found between male and female smile parameters except modified smile index.

Effect of maxillary median diastema on the esthetics of a smile

INTRODUCTION

With the increasing demand for facial esthetics, patients' expectations regarding dental treatment have increased. The treatment of maxillary median diastemas (MMDs) stands out as one of the most noticeable esthetic alterations performed on patients. The objectives of the present article were to evaluate the effects of MMD and its restorations on the esthetics of a smile and to determine the differences in esthetic perceptions among 3 different groups of patients: orthodontists, prosthodontists, and laypeople.

METHODS

Printed photographic images were randomly arranged in an album that contained the original photograph of the smile, 8 photographs with digitally created diastemas (0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 4.0 mm, and 5.0 mm), and 8 with simulated restorations of these spaces. Each evaluator assigned scores to the images using a 100-mm visual analogue scale.

RESULTS

Orthodontists, prosthodontists, and laypeople presented similar perceptions regarding the levels of attractiveness of the original smiles and those of smiles involving restorations of diastemas with widths of 0.5 mm and 1.0 mm. The ratings assigned to the smiles with diastemas differed significantly from those of the corresponding restored smile with the same magnitude of diastema.

CONCLUSIONS

The prosthetic space closure of diastemas is better than leaving the space untreated. Restorations of MMD up to 1 mm perform similar to orthodontic closure. Larger MMDs are ideally treated with orthodontics because the restorative treatment is more invasive, leading to incremental damage to the dental tissues.

The ideal auricular protrusion - An interactive perceptual pilot study

PURPOSE

Excessive ear protrusion (prominauris) can negatively affect facial appearance. Because the concept of an ideal auriculocephalic angle is controversial, however, it is difficult to define when an obtrusive auricle requires surgical intervention. It is often assumed that angles exceeding 30° require corrective surgery. However, little is known about public perception of ear protrusion. This study aimed to assess perceptions of different degrees of auricular protrusion.

MATERIALS AND METHODS

We conducted an interactive panel survey. Male and female evaluators assessed digitally processed cloned images of a male and female model that depicted various ear protrusions ranging from 0° to 90°. Predictor variables were the sex of the evaluator, the sex of the clone and the extent of auricular protrusion. The outcome variable was the overall attractiveness of auricular appearance.

RESULTS

Forty-four evaluators (students of dental medicine, mean age 25.43 years) participated in the study: 22 women and 22 men. The study results revealed sexual dimorphism, with the attractiveness of corresponding male and female clones rated differently. Male evaluators favoured female ear positions that fitted closer to the head; preferred alignments for female clones were: 18° (Mean) ± 9.38° (SD), p = 0.006; for male clones: 30° ± 7.94°, p = 0.003. Ear protrusion starts to negatively affect aesthetic appearance for male evaluators at positions of 42° ± 4.87° (female clone) and 54° ± 8.22° (male clone), p = 0.001. The panel of evaluators agreed to perceive angles of 21-24° ± 8.10° (female clones), ± 8.33° (male clones), as the ideal degree of protrusion in both sexes (p = 0.158).

CONCLUSION

In this study, perception of ear appearance depended on the sex of both the evaluator and the clone being assessed. Obtrusive ears were more readily accepted in male faces than in female ones. Nevertheless, the overall panel perception shows a preference for rather close fitting, unobtrusive ear alignments. For planning of corrective ear surgery, a target angle of approximately 22° can be considered as a desirable result.

Perception of Buccal Corridor Space on Smile Aesthetics among Specialty Dentist and Layperson

Objectives

The aim of this study was to assess and compare the perception of smiles with and without buccal corridor spaces (BCSs) among prosthodontists, orthodontists and laypersons on smile aesthetics.

Materials and Methods

Smiling photographs of subjects with wide BCSs were collected and digitally manipulated to eliminate the BCSs. Digitally altered and unaltered photographs were placed together and assessed for aesthetic appeal using visual analog scale of one to ten by prosthodontists, orthodontists, and laypersons. One-way analysis of variance (ANOVA) and two-way ANOVA were applied to evaluate the collected data using the Statistical Package for the Social Sciences (SPSS 22), Epi Info 6.0, and GraphPad Prism, version 6.0.

Results

The total mean value scores of smiles with BCSs were significantly higher than those of smiles without BCSs (P < 0.001). Orthodontists and prosthodontists significantly appreciated BCSs and graded the smiles with BCSs to be much more attractive (P > 0.005). Laypersons rated the smiles with BCSs with greater mean values, but the difference in mean values of smiles with and without BCSs was not significant (P < 0.005). No significant difference was found between the perceptions of prosthodontists and orthodontists.

Conclusion

The results of this study reveal that the smiles with BCSs were notably more desirable than the smiles without BCSs. Laypersons, orthodontists, and prosthodontists evaluated smiles differently. The smiles with BCSs were appraised much more pleasing by prosthodontists and orthodontists. Laypersons could not significantly appreciate BCSs, but rated smiles with BCSs as more acceptable.

Perception of general dentists and laypersons towards altered smile aesthetics

OBJECTIVES:

This study aimed to evaluate how dental practitioners and laypersons differ in their perception of altered smile aesthetics based on viewing images of a digitally manipulated smile.

MATERIALS AND METHODS:

A photograph with close to ideal smile characteristics was selected and digitally manipulated to create changes in buccal corridor space (BCS), midline diastema, gingival display, and midline shift. These altered images were rated by two groups: dental practitioners and lay persons using a visual analogue scale. The mean ± standard deviation (SD) of both groups were calculated and the Student's t-test was used to identify any statistically significant differences between the groups. Data analysis was done using the Statistical Package for Social Science (version 23.0; SPSS Inc., Chicago, Illinois, USA).

RESULTS:

The dentists were more sensitive to changes in the midline shift than laypeople and provided lower scores. There were no significant differences between the two groups when the gingival display alteration was ≤3 mm. However, for gingival display of 4 mm and 5 mm, there was significant difference between the two groups, with dentist rating them poorer as compared with the laypeople (P < 0.001). Dentists were more sensitive than the laypeople for midline diastema of 2 mm and 3 mm (P < 0.001 and P = 0.005 respectively). Changes in the BCS had minimal impact on the overall esthetic score for both the groups.

CONCLUSIONS:

Perception of smile esthetics differed between dentists and laypersons.

Perception of Professional Female College Students Towards Smile arc Types and Outlook about their Appearance

Aims and Objectives

The aim of this study is to assess the perception of female students about the type of smile arc as well as their outlook about different parameters of esthetics.

Materials and Methods

A study was conducted among female students of King Khalid University, Abha, Saudi Arabia. One section of the questionnaire contained pictures having three types of smile arc wherein the respondents had to select any response ranging from 1 to 4 (1 for beautiful, 2 for good, 3 for average, and 4 for poor); besides it included 12 questions regarding the viewpoints of respondents about their smile and dental esthetics. The collected data were analyzed using the statistical package for social services version 16.0 (SPSS Inc., Chicago, IL, USA, 2001).

Results

The dental students accounted for least mean score of 1.807 ± 0.8174 for consonant smile arc while it was 2.692 ± 0.8053 and 2.235 ± 0.9074 for information technology (IT) and medical students, respectively. When the individuals were asked whether they had a pleasant smile or not; only 53.8% of the dental students, 76.9% of the IT students, and 66.7% of the medical students responded positively.

Conclusion

It was concluded that most of the female dental students were able to identify the consonant smile arc as being more beautiful than the flat and reverse smile arcs whereas lesser medical and IT students could perceive the smile arcs in the same manner. It was also observed that almost all the study participants were quite conscious about their smile attractiveness and dental esthetics.

Perception of smile esthetics by laypeople of different ages

BACKGROUND

Age is a factor affecting smile esthetics. Three variables of smile esthetics associated with the maxillary anterior teeth and age-related changes have recently received considerable attention: (i) the incisal edge position of the maxillary central incisors, (ii) the maxillary gingival display, and (iii) the presence of a black triangle between the maxillary central incisors. The aim of this study was to evaluate the influence of age on smile esthetic perception based on these three variables in a group of Thai laypeople.

METHODS

The smiles were constructed from a photograph of a female smile. Smile photographs were altered in various increments using three variables: the incisal edge position of the maxillary incisors, gingival display, and a black triangle between the maxillary central incisors. The photographs were shown to a group of 240 Thai laypeople. The subjects were divided into two groups: a younger group, 15-29 years old (n = 120) and an older group, 36-52 years old (n = 120). Each subject was asked to score the attractiveness of each smile separately using a visual analog scale.

RESULTS

Smile attractiveness scores concerning the incisal edge positions of the maxillary central incisors were similar between the two groups. However, upper lip coverage was rated as unattractive by the younger group. A gingival display of 0 and 2 mm was rated as most attractive by the younger group. Upper lip coverage and gingival display of 0 and 2 mm were considered attractive by the older group. Excessive gingival display (6 mm) was scored as unattractive by both groups. A black triangle ranging from 1 to 2.5 mm between the maxillary central incisors was scored differently between the two groups. The older group was more tolerant of the black triangle size.

CONCLUSIONS

Age impacts smile perception based on maxillary gingival display and the presence of a black triangle between the maxillary central incisors, but not of the incisal edge position of the maxillary central incisors. Due to the variation in esthetic perception of each individual, participation between orthodontists and patients for decision-making and treatment planning is a crucial process to provide successful results.