Influence of dental midline deviation with respect to facial flow line on smile esthetics-A cross-sectional study.

BACKGROUND/OBJECTIVE: A contemporary concept states that dental midline deviation towards the direction of facial flow line (FFL) can mask the compromised smile esthetics. This study aimed to identify a range of midline deviations that can be perceived towards or away from the FFL influencing smile esthetics. MATERIALS AND METHODS: A cross-sectional study was conducted using a frontal smile photograph of an adult female. The photograph was altered on Adobe Photoshop software into six different photographs by deviating the dental midlines towards and away from the FFL. A constant deviation of chin towards the left side was incorporated in all the photographs. Forty-three laypersons (LP) and dental professionals (DPs) evaluated those photographs. Independent t-test was used to compare the perception of dental midline deviation between LP and DPs. Simple linear regression was run to identify the factors associated with the scoring. RESULTS: A statistically significant difference was observed for picture two with 4 mm towards FFL in the perception of midline deviation between LP and DPs. LP could not perceive the midline deviations up to 4 mm while DPs were able to perceive deviations above 2 mm. The greater the age the better the scores were and female raters had a greater inclination towards poor scores. CONCLUSIONS: From 2 to 4 mm of midline deviation towards the FFL can be tolerated by LP and DPs. CLINICAL SIGNIFICANCE: These findings underscore the importance of considering facial symmetry in orthodontic and cosmetic dental treatments to optimize smile esthetics.

Impact of long contact areas for the management of varying levels of interdental papilla loss on the perception of smile esthetics between dentists and laypersons in asymmetric and symmetric situations.

PURPOSE: To determine the effect of restorations with long contact areas for the management of interdental papilla deficiencies, in smile attractiveness among laypersons and dentists. MATERIAL AND METHODS: A full-portrait image was used to create a set of digitally modified images, simulating the management of various levels of interdental papilla loss. In a total of 48 modified images, single as well as multiple loss of interdental papilla among the anterior teeth, treated with a single or multiple restorations were simulated for unilateral and bilateral situations. Through a digital monitor 160 laypeople and dentists were asked to assess the attractiveness of each displayed image utilizing a visual-analog-scale. Multiple Wilcoxon-signed-rank tests followed by Mann-Whitney U tests were performed considering a significance level of 0.05. RESULTS: The management of an open gingival embrasure due to interdental papilla loss, by simulating the restoration of both central incisors led to a significantly higher mean smile attractiveness compared to the restoration of a single central incisor. Among the investigated regions, the management of open gingival embrasure in the area of central incisors using a restorative approach was perceived as the least esthetic (p < 0.05). CONCLUSIONS: Despite the restorative management of interdental papilla loss, with the establishment of longer contact areas for the reduction of open gingival embrasures, as the level of the interdental papilla loss is increased, facial esthetics are compromised. When a longer contact area is accomplished through a single restoration, asymmetry among the teeth can be induced, especially in the region of the central incisors.

What comes first: teeth or face? Recommendations for an interdisciplinary collaboration between facial esthetic surgery and dentistry.

OBJECTIVE: The aim of the present study was to provide recommendations in order to facilitate communication between dental professionals and surgeons who are collaborating in the field of dentofacial esthetics. CLINICAL CONSIDERATIONS: Smile esthetics are beyond the scope, both of the surgeons who are collaborating with facial esthetics and of the dentists, as a wide range of treatment options from both sides is available. It can be difficult for the surgeon or the dentist that first comes in contact with the patient to conduct an individualized global treatment plan, in order to find out how the various phases of the treatment can be sequenced, as a workflow for an efficient interaction between facial surgery and dentistry still does not exist in the scientific literature. CONCLUSIONS: Facial cosmetic procedures and dental treatment have to be planned as individual elements of the whole dentofacial esthetic rehabilitation. The treatment has to be initiated with the design of the smile and the intraoral mock-up, followed by the required surgical interventions, and to be finished with the delivery of the definitive dental restoration. CLINICAL SIGNIFICANCE: Dentofacial esthetics require comprehensive communication between surgeons and dentists. Following the proposed recommendations, an individualized interdisciplinary treatment plan can be conducted, defining the role of each specialty.

Changes in smile parameters after surgical-orthodontic treatment for skeletal Class III malocclusion.

Background/purpose: Many patients pursue attractive smiles, and surgical-orthodontic treatment is a common method. We aimed to analyze the changes in smile parameters after surgical-orthodontic treatment in patients with skeletal Class III pattern and identify factors influencing postoperative outcomes. Materials and methods: This retrospective study comprised 34 patients with skeletal Class III malocclusion and pure mandible prognathism who received surgical-orthodontic treatment. Hard and soft tissue parameters were assessed through lateral cephalometry, and smile esthetics were evaluated through extraoral photography. Postoperative changes in smile parameters and between-parameter correlations were analyzed. Random forest and decision tree deep learning models were used to identify factors influencing postoperative changes. Results: Substantial postoperative changes were observed in the buccal corridor, upper lip height, and smile index. Significant between-sex differences were noted in the upper midline and right chelion. Strong, positive correlations were found between upper lip height and upper lip ratio and between lower lip height and lower lip ratio. By contrast, strong negative correlations were observed between lower teeth exposure and smile index and between interlabial gap and smile index. The highest degrees of postoperative changes were noted in asymmetry-associated smile parameters: lower lip area, interlabial gap, smile index, buccal corridor, and arc ratio. Conclusion: Considerable changes were noted in skeletal, dental, and soft tissue parameters after surgical-orthodontic treatment. However, the changes in smile esthetics were less prominent from the frontal view. As for chin asymmetry, the most to least prominent changes were in the lower lip area, interlabial gap, smile index, buccal corridor, and arc ratio, respectively.

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.

The Influence of a Single Infrapositioned Anterior Ankylosed Tooth or Implant Supported Restoration In Smile Attractiveness.

OBJECTIVES: To investigate the influence of a single infrapositioned ankylosed tooth or implant supported restoration, in smile attractiveness. MATERIAL AND METHODS: A series of 48 digital modified images, simulating a varying degree of infraposition(from 0.25 to 2.0 mm, with a step of 0.25 mm), was created for each one of the maxillary anterior tooth, by altering the full-portrait image of a smiling male adult, in medium and high smile lines. For the model with the high smile line, also a series of 24 digital modified images simulating infraposition of a single anterior tooth with a restored incisal edge was created. Smile attractiveness for each one of the images was evaluated from 160 participants (80 dentists and 80 laypersons), implementing a visual analog scale. RESULTS: For the images with the high smile line, an infraposition ≥ 0.25mm in central incisor's region and ≥ 0.5mm in the region of the lateral incisor or the canine, had a negative effect on the perceived smile attractiveness both for the dentists and the laypersons. Regarding the medium smile line, an infraposition ≥ 0.5mm in central and lateral incisor's region, had a negative effect on the perceived smile attractiveness for both groups of observers. In the area of the canine, infraposition ≥ 0.5mm for the dentists and ≥ 0.75mm for the laypersons, had a negative impact on the smile attractiveness. CONCLUSIONS: Even a minor infraposition of a single maxillary anterior ankylosed tooth or implant supported restoration, can reduce the perceived attractiveness of the face. Infraposition in canine's area can be better tolerated in a medium, compared to a high smile line. In patients with a high smile line prosthetic intervention in order to restore the incisal edge of an infrapositioned tooth, without to harmonize the gingival contour, can be beneficial for the lateral incisor, ineffective for the central incisor and unfavorable for the canine.

Factors affecting perception of laypeople and dental professionals toward different smile esthetics.

Abstract Background: /purpose: Several factors such as identity, income, and age potentially associated with smile perceptions. This study aimed to identify the factors affecting the smile esthetic perception in different identities (layperson, general dentist and orthodontist) and to detect the extent of their association with smile perception. Materials and methods: Extraoral photographs in frontal, lateral, and three-quarter views were shot and adjusted on Adobe Photoshop into 95 smile photographs with different smile patterns. Based on these photographs, the investigators were asked to fill the online questionnaire. Pearson chi-square test and logistic regression were used for statistical analyses. Results: Identity, gender, age, and treatment experience were noted to affect smile esthetic perception. In addition, the perception of smile esthetics was significantly different among frontal, lateral, and three-quarters views regarding the arc ratio, most posterior teeth exposure, upper teeth exposure, and lower teeth exposure. Conclusion: Identity, gender, age, and treatment experience influence the smile esthetics perception, with a significant difference in the results of the esthetic perception based on the 3 smile views. Of all demographic factors, identity had a strong relation to the perception of smile attractiveness. Nevertheless, additional studies are needed to realize how the demographic factors influence people's perception of smile esthetics, particularly in the three-quarter and lateral views.

A coupled-lines system to determine the anteroposterior position of maxillary central incisors for smiling profile esthetics.

OBJECTIVES: To develop a coupled-lines system to determine the anteroposterior position of maxillary central incisors (U1) for smiling profile esthetics. MATERIALS AND METHODS: Thirty Asian females with ordinary and good facial harmony were selected as the study sample and the control sample, respectively. Three-dimensional facial images and 45°- and 90°-angled profiles were collected. The anteroposterior relationships between U1 and upper- and mid-facial soft tissue landmarks were measured. By morphing photos of the study sample, two artificial images were created to represent the well-balanced 45°- and 90°-angled profiles and were further processed with combined variations of soft tissue subnasale (SSn)-Glabella and the mid-point of facial axial points of the bilateral central incisor (mFA)-SSn distances. Esthetic assessments were performed on these images by layperson (n = 94) and orthodontist (n = 94) raters. RESULTS: Both upper- and mid-facial soft tissue landmarks were indispensable in assessing anteroposterior positions of U1 for well-balanced smiling profiles. As assessed in 45°- and 90°-angled profiles, the most esthetically sensitive parameters were mFA-Glabella and mFA-SSn distances. A coupled-lines system was constructed, comprising the Glabella and SSn vertical lines. In smiling profiles with optimal esthetics, the mFA point was at 2 to 5 mm posterior to the Glabella vertical and concomitantly 4 to 7 mm posterior to the SSn vertical, as perceived by orthodontists. Laypersons gave a wider range for mFA-Glabella distances, at 2 to 6 mm. CONCLUSIONS: The coupled-lines system could serve as a reliable reference for determining esthetically optimal anteroposterior positions of U1 for female facial profiles.

Effect of smile esthetics on the quality of life in a Han Chinese population.

OBJECTIVE: This study aimed to explore the influence of smile esthetics on the quality of life in a Han Chinese population. METHODS: A total of 110 Han Chinese volunteers (52 males and 58 females, mean age 26.7 years) were recruited, and frontal images of their smiles were collected. A photoediting program was used to evaluate the following components of smile esthetics: the buccal corridor ratios, the angle between the interpupillary and commissural lines, the number of visible teeth, and width-to-length ratios of the maxillary central incisors. Oral health-related quality of life (OHRQoL) in these volunteers was evaluated using the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) and Oral Health Impact Profile-14 (OHIP-14). Statistical analyses were performed by using Pearson's correlations and multiple linear regression (α = 0.05). RESULTS: Compared to males, females scored higher on psychological impact (p = 0.017). Moreover, the number of visible teeth had a significant effect on social impact, psychological impact and esthetic concern (all p < 0.05). However, the buccal corridor ratios, the angle between the interpupillary and commissural lines, and the width-to-length ratios of the maxillary central incisor did not correlate with the OHRQoL (all p > 0.05). CONCLUSIONS: The number of visible teeth significantly influenced the quality of life in a Han Chinese population. Smile esthetics had a significantly greater psychological impact on females than males. CLINICAL SIGNIFICANCE: This study highlights the effects of smile esthetics on the quality of life in a Han Chinese population. Female patients may raise more esthetic concerns in clinical practice.

An Assessment of the Accuracy of Recurring Esthetic Dental Proportion: An In Vivo Comparative Analysis of Maxillary Anterior Teeth Proportion With Chu's Gauge and Custom-Made Calipers.

Smile designing, in harmony with nature, has always been a challenge in dentistry. Several theories have been proposed in the past with a view to replicate an esthetic smile. One such method proposed by Dr. Chu involves using the recurring esthetic dental (RED) proportion. He designed a scale for calculating the average values for the height and width of upper anterior teeth for a specified population. However, whether this average is valid for other populations has not been verified. Hence, this study was conducted to evaluate if Chu's gauge value agrees with the dimension of anterior teeth in the South Indian population. The study involved 362 subjects whose anterior teeth dimension was assessed using Chu's gauge and a custom-made caliper. The proportion of the population whose dimension aligns with the average values on Chu's gauge was evaluated. The results showed that in the cohort, 39% had their central incisor dimension coinciding with the red band of Chu's esthetic scale, 10% had their lateral incisor coinciding with the blue band of Chu's esthetic scale, and 6.4% of the subjects had their canine dimension coinciding with the yellow band of Chu's esthetic scale.

Botulinum Toxin and Smile Design.

Smiles with excessive gingival display exceeding 3 mm are considered unattractive. Excessive muscular contraction of lip elevator muscles is the etiology in most cases, and other factors, such as excessive vertical dimension of the maxilla and altered passive dental eruption resulting in the presence of excessive gingival tissue, account for the etiologic factors in others. Botulinum toxin type A (BTX-A) blocks muscular contraction by inhibiting the release of acetylcholine in muscles' endplates. The author has proven BTX-A to be an effective treatment alternative for the correction of these conditions affecting smile esthetics. This article explains how this is accomplished.

Contemporary Smile Design: An Orthodontic Perspective.

Orthodontists play a vital role in the smile design of individuals. There are a variety of orthodontic goals and tooth movements that can be achieved to obtain the ideal smile that ultimately leads to the optimum esthetic outcomes. In this article, some methods and appliance systems to control and achieve the desired tooth movements are described and illustrated.

Botulinum toxin type A for the treatment of excessive gingival display - A systematic review.

Gummy smile has traditionally been treated with invasive or demanding surgical and orthodontic techniques. Several studies have shown that targeted injection of the upper lip elevator muscles with botulinum toxin is an effective treatment for this condition. However, no standardized injection protocol with reproducible results has yet been published. A systematic review of the literature has been performed using Medline, Scopus, and Embase. All articles relevant to the research question were analyzed. After removing duplicates, 162 articles were selected, of which 9 were included in the analysis after applying exclusion and inclusion criteria, for a total of 269 patients. Onabotulinum toxin type A (ONA-BoNTA) was used in 7 studies and abobotulinum toxin type A (ABO- BoNTA) in 2 studies, at various dilutions. The number of sites injected varied from 1 to 3 per side, with variable targeting of the Levator labii superioris alaeque nasalis, Levator labii superioris, Zygomaticus minor, Zygomaticus major and Orbicularis oris. The dose used per side varied from 1.25 to 6 U of ONA-BoNTA and from 2.5 to 7.5 U of ABO- BoNTA. The injection protocol was tailored to the type of gingival smile in one study only, another study compared results of targeting two different muscles, and one study evaluated different dosages of toxin for the same injection site. The average improvement ranged from 24.85% to 99.65% and the effect persisted from 12 to 36 weeks. Very good patient satisfaction was reported in 6 studies. Fourteen adverse events were reported, all of them mild and transient. The treatment of gummy smile by botulinum toxin injection is effective, safe, rapid, minimally invasive and reversible. Protocols vary widely in the literature and no standardized procedure emerges. A patient-specific approach, adapted to their anatomy, type of gummy smile and the severity of the exposure seems to be the most appropriate. Randomized controlled studies are needed to make this approach more systematic.

Influence of facial type on attractiveness of vertical canine position from the perspective of orthodontists and laypeople.

OBJECTIVES: To evaluate the attractiveness of changes in vertical position of maxillary canines in frontal smiles of different facial types, and to evaluate the esthetic perceptions of orthodontists and laypeople, and the influence of facial type on these perceptions. MATERIALS AND METHODS: Three adult female volunteers were selected as individuals with normal, vertical, and horizontal growth patterns. Frontal posed smile photographs were digitally altered by adjusting vertical positions of the maxillary canines above, below, or coincident with the incisal line in increments of 0.5 mm within a range of 1 mm of extrusion and intrusion. For assessment, a web-based survey was formed with 18 images (six images for each model). A scale was present underneath each image, graded from 0 to 10 (0: unattractive; 10: the most attractive). Images were rated by 233 participants (105 orthodontists; 128 laypeople). RESULTS: Orthodontists scored 0-mm images significantly as the highest in all groups. Laypeople scored significantly higher for -0.5 mm images regardless of facial type. The lowest scored images were -1 mm (except for horizontal pattern) and +1 mm images. Mean values of scores given by men were higher (P < .05). CONCLUSIONS: Orthodontists favored ideal dental alignment and preferred the incisal edges of central and canine teeth to be at the same level. Laypeople preferred a smoother smile arc than orthodontists and found harmony with the soft tissue more attractive. Facial type affected perceptions of the vertical changes of maxillary canines.

Agenesis of maxillary lateral incisors: diagnosis and treatment options

ABSTRACT Introduction: There are different possibilities of orthodontic planning for cases with congenital absence of maxillary lateral incisors. This subject divides the opinion of orthodontists and oral rehabilitation clinicians, due to the advantages and disadvantages of each treatment option, which may involve opening spaces for future implants and/or prosthetic restorations, or closing the spaces by positioning the maxillary canines in the place of lateral incisors. The correct diagnosis and careful evaluation of each patient allow to determine the best therapeutic approach. This paper discusses the main topics to be considered when planning these cases. Objectives: To evaluate the main aspects related to orthodontic treatment planning in cases of congenital absence of maxillary lateral incisors, to aid the decision-making, with clinical and scientific basis.

RESUMO Introdução: Existem diferentes possibilidades de planejamento ortodôntico para os casos que apresentam ausência congênita de incisivos laterais superiores. Esse é um assunto que divide a opinião de ortodontistas e reabilitadores orais, devido às vantagens e desvantagens de cada uma das opções de tratamento, as quais podem envolver a abertura de espaços para futuros implantes e/ou restaurações protéticas ou o fechamento dos espaços, com posicionamento dos caninos superiores no lugar dos incisivos laterais. O correto diagnóstico e uma criteriosa avaliação de cada paciente permitem determinar a melhor abordagem terapêutica. Nesse artigo, serão discutidos os principais tópicos a serem considerados no planejamento desses casos. Objetivos: Avaliar os principais aspectos relacionados ao planejamento do tratamento ortodôntico nos casos de ausência congênita de incisivos laterais superiores, de maneira a auxiliar nas tomadas de decisão, com embasamento clínico e científico.

Effect of anterior overbite malocclusion on smile esthetics in adult patients.

OBJECTIVE: To investigate whether overbite affects smile esthetics. METHODS: This study involved 106 patients with complete pretreatment records. Lateral cephalometric tracings were used to measure hard tissue variables. Frontal smile and upper occlusal photographs were used to measure nine smile esthetic variables: arc ratio, number of teeth, upper incisor exposure, upper midline, buccal corridor ratio, smile index, archform index, lower teeth exposure, and interlabial gap. The patients were classified into three groups according to their overbites (B1: 0-4 mm, B2: >4 mm, and B3: <0 mm). Analysis of variance was performed to compare 14 cephalometric measurements and the 9 smile esthetic variables. Multiple linear regression analysis was performed to determine the influencing cephalometric factors. RESULTS: Only upper incisor exposure was significantly different among the groups. In the multiple linear regression analysis, upper incisor exposure was positively associated with the distance from the upper incisor to the palatal plane in Group B2. No significant correlations were observed between cephalometric measurements and smile variables in Groups B1 and B3. CONCLUSIONS: Smile variables were not significantly different among patients with various overbite malocclusions with the exception of upper incisor exposure. Overbite malocclusions do not appear to influence smile esthetics in adult patients.

The effect of botulinum toxin A in patients with excessive gingival display with and without zinc supplementation: randomized clinical trial.

OBJECTIVE: The objective is to determine the effect of oral zinc supplement intake on the clinical efficacy and sustained effect of BTXA injection, in patients with excessive gingival display (EGD). MATERIALS AND METHODS: Twenty-five participants with excessive gingival display (EGD) were included in this parallel-group RCT, treated with BTXA with and without Zinc supplementation prior to treatment. Participants were assessed for excessive gingival display reduction and results of stability at 2, 6, 12, 18, and 24 weeks. Patient satisfaction questionnaires were filled at 2, 12, and 24 weeks. RESULTS: The results of this study revealed that after 6, 12, 18, as well as 24 weeks; The control group (BTXA) showed statistically significantly higher median gingival display than the intervention (Zinc supplement with BTXA). In the intervention group, the median gingival display after 24 weeks showed statistically significantly lower median value compared to the baseline measurement CONCLUSIONS: The use of zinc supplementation prior to BTXA injection prolonged its effect and maintained long-term decreased amount of gingival display, and it did not return to baseline measurements. Patients reported high satisfaction levels and self-confidence. CLINICAL RELEVANCE: Botulinum Toxin A (BTXA) is used to correct gummy smile; however, its main drawback is its short-lasting effect. Oral zinc supplement intake prior to BTXA injection could maintain the effect of BTXA and enhance its clinical efficacy.

The Relationship between Posttreatment Smile Esthetics and the ABO Objective Grading System: Class I Extraction versus Non-Extraction Cases.

OBJECTIVE: This study aimed to evaluate the relationship between the components of the objective grading system developed by the American Board of Orthodontics (ABO) and smile esthetics in Class I extraction vs non-extraction cases. METHODS: A total of 40 extraoral smile images of orthodontically treated (20 extraction and 20 non-extraction) cases in the age group of 13-30 years and Class I skeletal malocclusion with an average mandibular plane angle were selected. Smile images were rated only by the orthodontist, and this panel included 12 members. Scoring of post-treatment dental casts and panoramic radiographs of each patient was performed by 1 investigator per the guidelines of the ABO grading system. The Pearson correlation coefficient and logistic regression analysis were used to ascertain whether the scores of the ABO grading system could foretell whether a smile would be "attractive" or "unattractive." RESULTS: The correlation between all the criteria of the ABO grading system and attractiveness of the smile was extremely weak. The r values ranged from -0.53 to 0.37 for extraction cases and -0.63 to 0.003 for non-extraction cases (p>0.05). Neither individual parameters nor total scores of the ABO grading system could predict whether the smile was attractive or unattractive in either group. CONCLUSION: No correlation was found between post-treatment ABO grading and smile esthetics in patients with extraction or non-extraction. Hence, this study recommends that ancillary soft tissue variables have to be incorporated into the grading system to evaluate a smile.

Do various degrees of tooth decalcification affect orthodontists', general dentists' and laypersons' ratings of smile esthetics?

OBJECTIVES: To compare the effect of various degrees of decalcification after orthodontic treatment (white spot lesions) on orthodontists', general dentists', and laypersons' ratings of smile esthetics. MATERIALS AND METHODS: Eight photographs representing incrementally altered tooth decalcification lesions of maxillary anterior teeth ranging from mild to severe were shown randomly to the study participants. Photographs were rated by a matched sample of orthodontists (N = 42), general dentists (N = 52), and laypeople (N = 58). A visual analogue scale (VAS) was used to assess perceptions of smile esthetics. RESULTS: The three groups of raters could distinguish between different decalcification levels. Raters gave more negative scores as the decalcification level increased. CONCLUSIONS: The three groups of raters were able to distinguish between various degrees of decalcification lesions. General dentists were the most critical of all groups when rating decalcification lesions.

Evaluation of the perception of smile esthetics, in frontal view, with mandibular laterognatism, through the eye-tracking technique.

OBJECTIVES: To evaluate the perception of esthetics and the attractiveness of the smile, in frontal view, with mandibular asymmetry, through the eye-tracking. MATERIALS AND METHODS: OGAMA software and The Eye Tribe Tracker hardware were used to obtain eye tracking in certain areas of interest on the face. To simulate asymmetry, Photoshop® image editing software was used to create a vertical reference line to the midline of the face and make it symmetrical with control of the angulation relative to another horizontal reference line passing through the vertices. Then, the lower third of the face added asymmetries or deviations, starting from zero, with increments of 2 by 2 degrees up to 6 degrees. The study included 60 laypeople, 30 males and 30 females, without any knowledge about the study, showing good vision, and not having used drugs with the possibility of influencing cognitive or motor skills. RESULTS: From the heat map in cases of mandibular asymmetry, it is possible to visualize that for both sexes the evaluators evaluated with a certain degree of similarity mainly when the deviations presented with 6 degrees. The trajectory of the male and female gaze in cases with asymmetry shows that in cases with a magnitude of 6 degrees, the raters traced mainly in the region of the mouth with little transition in the eye region and mainly in the areas of interest considered as "other." In the images presented with a magnitude of up to 4 degrees, they were traced in the general image. CONCLUSIONS: The perception of laypeople from mandibular asymmetry to the right in females presented a higher perception when compared to males with mandible asymmetry to the left.