Perception of Altered Smile Esthetics by Orthodontists, Dentists, and Laypeople in Riyadh, Saudi Arabia

Laypersons' Assessment of Smile Esthetics in Young Individuals in Ha'il, Saudi Arabia

INTRODUCTION

When planning esthetic dental treatments, understanding smile preferences is important for dental professionals. This study aimed to evaluate the impact of selected smile characteristics on the attractiveness of young Saudis as assessed by Saudi laypersons and explore gender-preferred changes in smile attractiveness.

METHODOLOGY

This observational study assessed the dynamic smile attractiveness of 168 Saudi individuals (84 males and 84 females), selected through non-probability convenience sampling. Dynamic smiles were elicited by viewing comedic content and captured with a camera standardized for consistent positioning. Videos were edited and adjusted to images, and the frames with the most pronounced smiles were chosen. The intra-rater reliability was assessed using intra-class correlation coefficients (ICCs) and Cohen's kappa tests (κ). The highest and lowest 25th percentiles were categorized as attractive and unattractive smiles, respectively, on the visual analog scale (VAS) by laypersons. Six smile characteristics - anterior smile line, smile arc, upper lip curvature, posterior teeth displayed, smile index, and smile symmetry - were quantitatively evaluated from these images for each participant and classified into attractive and unattractive groups based on laypersons' VAS evaluations. Continuous variables were tested with the Mann-Whitney U test, and for the categorical variables, the Chi-square test was applied. The significance was set at 5%.

RESULTS

 The four randomly selected out of the 22 raters had good VAS reliability; ICCs varied from 0.661 to 0.94, with an average of 0.737, and Cohen's kappa tests for smile characteristics showed values from 0.617 to 0.89. Good agreement was also found with the smile index, with ICCs of 0.775, and dynamic smile symmetry, with ICCs of 0.872. Laypersons rated female smiles as more attractive compared to male smiles (P = 0.004). Low or average anterior smile lines (P = 0.001 for males; P = 0.03 for females), parallel smile arcs (P = 0.001 for males; P = 0.02 for females), and higher smile indexes (P = 0.001 for males; P = 0.004 for females) were significantly attractive, showing no significant gender differences.  Conclusions: Laypersons reliably rated the young Saudis' dynamic smiles as attractive. Of the rated smile characteristics, those with a low or average anterior smile line, parallel smile arcs, and a larger smile index were deemed more attractive. This study's findings show no significant gender differences in the impact of the studied smile characteristics on attractiveness. This study's findings can help dental professionals customize treatment plans that meet patients' expectations.

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.

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.

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.

Smile Attractiveness and Treatment Needs of Maxillary Midline Diastema with Various Widths: Perception among Laypersons, Dental Students, and Dentists in Malaysia

Smile attractiveness and the need for treatment of maxillary midline diastema with various widths are perceived differently between dentally trained and nondentally trained individuals of different sociodemographic backgrounds. This study aims to evaluate how laypersons, dental students, and dentists in Malaysia differ in their perceptions on smile attractiveness and treatment needs of maxillary midline diastema. A smiling photograph with well-aligned maxillary central incisors with proportionate width-to-height ratio and healthy gingival tissues was selected and digitally manipulated to create maxillary midline diastema with 0.5, 2.0, and 4.0 mm widths. The smile attractiveness and the perceived need for treatment of varying widths of maxillary midline diastemas were rated by laypersons, dental students, and dentists using the Likert scale via a single set of self-administered questionnaires. The impact of sociodemographic variables on aesthetic perception of different gap widths was tested using univariate analysis followed by a multiple linear regression model. A total of 158 laypersons, 118 dental students, and 138 dentists participated in this study. Both laypersons and dentists showed significantly higher mean aesthetic scores for 0.5 mm maxillary midline diastema, lower mean aesthetic scores, and hence higher mean treatment needs scores for 4.0 mm maxillary midline diastema as compared with dental students (p < 0.05). In general, female respondents perceived a gap width of up to 2.0 mm as aesthetically pleasing. Higher educational group and the Malay ethnicity had tolerance threshold of 0.5 mm gap width. The older group considered 4.0 mm gap width as aesthetically unpleasing. In conclusion, both laypersons and dentists accepted a 0.5 mm maxillary midline diastema as an attractive smile but considered 4.0 mm maxillary midline diastema as unpleasing smile which required treatment. Perceptions of laypersons and dentists were significantly different from dental students. Educational level, gender, ethnicity, and age were significantly associated with smile attractiveness of maxillary midline diastema at different investigated widths.

Subjective and Objective Evaluation of the Symmetry of Maxillary Incisors among Residents of Southwest Poland

Dental aesthetics is an essential factor affecting people’s psychosocial wellbeing. One of the most critical components of an aesthetic smile is symmetry within the dentition. Dentists and orthodontists, unlike laypersons, are critical in assessing dental aesthetics. This study aimed to evaluate the accuracy of patients’ assessment of the symmetry of their maxillary incisors and some factors that influence it. The study was conducted on 83 participants aged from 11 to 39 years. First, the participants filled out a questionnaire to obtain patients’ opinions of the symmetry of their upper incisors. This stage was followed by an intraoral examination, during which we used a digital caliper to measure the width of four maxillary incisors. The data were entered into STATISTICA v. 13.3. The following conclusions were drawn from the study. First, the respondents were generally able to determine the asymmetry of the incisors. Second, among the maxillary incisors, the participants defined the symmetry of maxillary central incisors more accurately than the maxillary lateral incisors. The cut-off value for incisor asymmetry noticeable to a layperson is 0.2 mm for maxillary medial incisors and 0.55 for maxillary lateral incisors. Third, we found no dependence of the accuracy of the assessment of incisor asymmetry on the age of the subjects; however, in our study group, the age range (spread) was not significant, so further studies are recommended. Finally, results concerning the relationship with gender showed that males assess the level of symmetry of their maxillary incisors more accurately than females.

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.