Influence of the Vertical Position of Maxillary Central Incisors on the Perception of Smile Esthetics Among Orthodontists and Laypersons

Clinical audit of an artificial intelligence (AI) empowered smile simulation system: a prospective clinical trial

Smile aesthetics is an important factor to consider during orthodontic treatment planning. The aim of the present study is to assess the predictability of Invisalign SmileView for digital AI smile simulation in comparison to actual smile treatment outcomes, using various smile assessment parameters. A total of 24 adult subjects (12 females and 12 males; mean age 22 ± 5.2 years) who chose to be treated using Invisalign were prospectively recruited to have their pretreatment smiles captured using the Invisalign SmileView to simulate their new smiles before treatment was started. Patients were then treated using upper and lower Invisalign aligners with average treatment time of 18 ± 6 months. Full post-treatment records were obtained and full smile frame images of simulated smile and actual final smile of each subject were evaluated by an independent examiner using an objective assessment sheet. Ten smile variants were used to assess the characteristics of the full smile images. Significance level was set at P < 0.05. The ICC for the quantitative parameters showed that there was an overall excellent & good internal consistency (alpha value > 0.7 & > 0.9). The Independent t test was performed amongst the quantitative variables. The P value was not significant for all except maxillary inter canine width (P = 0.05), stating that for the five variables namely; philtrum height, commissure height, smile width, buccal corridor and smile index, actual mean values were similar to the simulation mean values. For the qualitative variables, the Kappa value ranged between 0.66 and - 0.75 which showed a substantial level of agreement between the examiners. Additionally, the Chi square test for the qualitative variables, revealed that the P value was found to be significant in all except lip line. This implies that only the lip line values are comparable. More optimal lip lines, straighter smile arcs and more ideal tooth display were achieved in actual post treatment results in comparison to the initially predicted smiles. Five quantitative smile assessment parameters i.e., philtrum height, commissure height, smile width, buccal corridor, and smile index, could be used as reliable predictors of smile simulation. Maxillary inter canine width cannot be considered to be a reliable parameter for smile simulation prediction. A single qualitative parameter, namely the lip line, can be used as a reliable predictor for smile simulation. Three qualitative parameters i.e., most posterior tooth display, smile arc, and amount of lower incisor exposure cannot be considered as reliable parameters for smile prediction.Trial Registration number and date: NCT06123585, (09/11/2023).

Dental esthetic screening index (DESI) scores among patients attending Qassim University dental clinics

Aim

This study aimed to evaluate dental esthetic screening index (DESI) Intraoral component scores among patients attending Qassim University dental clinics and the factors affecting these scores.

Materials and methods

This was a retrospective study that included 150 participants aged 18 years or older with full upper and lower anterior dentitions. Standardized intraoral frontal photographs of the patients' upper and lower dentitions were acquired from their dental records, and the mean rank DESI intraoral scores were evaluated and compared across the demographic and dental characteristics of the study patients.The mean age of the patients sampled was 33.56; 57 % were female and 43 % were male. The mean DESI Intraoral score was 15.33. DESI scores were significantly higher in patients older than 35 years compared with subjects 35 years old or younger (p = 0.015). DESI scores were increased in patients who had anterior restorations compared with those who did not (p = 0.016).

Conclusions

This was the first study of its kind to use the DESI in a large clinical setting. According to the DESI, most patients attending Qassim University dental clinics had good dentofacial aesthetics. Age and the presence of anterior restorations negatively impacted patients' dentofacial aesthetics. Sex, the nature of the chief complaint, a history of orthodontic treatments, and teeth bleaching did not affect the DESI scores.

The knowledge regarding the impacts and management of black triangles among dental professionals and laypeople

This study aimed to assess the knowledge regarding impacts, causes and management of black triangles (BT) among participants from different educational backgrounds including dental students, dentists and laypeople. This descriptive cross-sectional observational research included 435 participants who comprised 4 groups: pre-clinical (3rd year) dental students, clinical (4th and 5th year) dental students, dentists, and laypeople. A constructed self-reported questionnaire was utilized to assess participants' demographic data and their knowledge of the impacts, causes and management of BT. The VAS scale was used to assess participants' ratings for the impacts of BT on esthetics, with 0 meaning no impact and 10 meaning very severe negative impacts. The most reported treatments for BT were "cannot be treated" 99.3% and "non-surgical periodontal treatment" 67.1%. Meanwhile, the least reported was "modify the porcelain" 41.8%. The most reported cause of BT was "periodontal disease" 85.1%. However, the least reported were "parafunction" and "deep implants" 33.1% each. Dental professionals had better knowledge of the causes (t = 8.189, P < 0.001) and management (t = 8.289, P < 0.001) of BT than the non-dental participants. The dentists had the best knowledge, while the laypeople had the least knowledge of the causes (F = 62.056, P < 0.001) and treatment (F = 46.120, P < 0.001) of BT. The knowledge of the causes (t = 0.616, P = 0.538) and treatment (t = 1.113, P = 0.266) for BT was not significantly different between males and females. Age was not significantly related to the total knowledge about the causes (r = -0.034, P = 0.475) or treatment (r = -0.034, P = 0.482) for BT. Dental professionals had better knowledge of the impacts, causes and management of BT than the non-dental participants. The dentists were the best, while the laypeople were the worst in this regard. Age and gender had no relationships with the knowledge of causes or management of BT.

Relationships between perception of black triangles appearance, personality factors and level of education

This analytical cross-sectional study evaluated the perception of black triangles (BT) and examined the relationships between the perception of BT, personality factors, different educational backgrounds and demographic factors. 435 participants were included and divided into four groups: dentists, clinical (4th and 5th year) dental students, pre-clinical (3rd year) dental students, and laypeople. Participants' perception of the attractiveness of smile profiles of maxillary and mandibular anterior dentition with BT was rated using a ten-point VAS scale with 0 being the least, and 10 being the most attractive smile profile. The personality was assessed using the NEO-FFI personality questionnaire. The smile profile with multiple large BT was rated the least attractive for the maxillary (mean = 3.6) and mandibular (mean = 3.9) tested profiles. The smile profile without BT was rated the most attractive for the maxillary (mean = 9.1) and mandibular (mean = 8.8) tested profiles. The dental professionals perceived the maxillary smile profile with multiple large BT as less attractive than the non-dental participants (t = - 2.715, P = 0.007). Being a male, having dental education, having lower Neuroticism scores, as well as having higher Openness, Agreeableness, Conscientiousness, and Extraversion scores predicted and contributed more towards perceiving various tested smile profiles as more attractive. These findings show that black triangles negatively impacts the perception of smile attractiveness, and that personality traits and having dental education impact the perception of smile attractiveness for smiles with black triangles.

The association between self-esteem and aesthetic component of smile among adolescents

OBJECTIVES

Self-esteem plays a crucial role during adolescence in a shaping of an individual's overall well-being and confidence. The aim of this study was to explore the relationship between the self-esteem in adolescents and their smile aesthetics, as well as to assess the alignment of opinions on this matter between adolescents and dentists.

METHODS

Sample included 413 students in Split-Dalmatia County, aged 13 to 18 (60% females). Data on demographic issues, orthodontic history, and desire for orthodontic treatment were collected by the self-administrated questionnaire. Coopersmith's Self-Esteem Inventory was also used. Smile aesthetics was assessed by each participant and dentist independently using an Aesthetic Component of the Index of Orthodontic Treatment Need (IOTN AC).

RESULTS

Self-esteem was higher in adolescents who rated their smile aesthetics equally to the dentist than in those who considered their aesthetics to be worse than the dentist (18.5 vs. 16; P = 0.011). The multiple linear regression revealed that the self-esteem of adolescents was positively related to undergone previous orthodontic treatment (β = 1.286, P = 0.020) while negatively related to the female gender (β = -2.531, P ≤ 0.001) and IOTN AC assessed by dentist (β = -0.356, P = 0.015). It was not related to educational level or desire for orthodontic treatment.

CONCLUSION

The self-esteem in adolescence is influenced the most by gender, but the orthodontic treatment and better smile aesthetics might also contribute.

[Aesthetic preferences of individuals when evaluating photographs of facial profiles with different sagittal and vertical growth patterns. A cross-sectional study]

Objective

To evaluate the aesthetic preferences of individuals by observing photographs of different facial profiles with different sagittal and vertical growth patterns.

Materials and Methods

Cross-sectional study that evaluated 300 students from a private university. Edited photographs of a man and a woman were used. The maxilla being moved in a vertical direction while the mandible was moved in a sagittal direction, various combinations of the photographic profile of the two individuals were created. These movements created 9 photographic profiles for the woman and the man; for intra-observer reliability, two photo profiles of both sexes were duplicated. Chi square tests and binary logistic regression were used. P<0.05.

Results

In general, the evaluated individuals mostly preferred the type 6 profile (65.7%), followed by the type 5 profile (21.7%) (slightly convex). It was found that for every year of age that an individual increases, there is a 31% greater chance of choosing one of these profiles.

Conclusions

Both sexes prefer a straight or slightly convex profile, and as age increases, individuals prefer a straight profile.

Aging changes in maxillary anterior teeth in untreated individuals: an observational longitudinal study

OBJECTIVE

The aging of the occlusion and tooth wears influence the smile design This study aimed at evaluating the aging changes of maxillary anterior teeth in nontreated subjects.

METHODS

The sample comprised dental models of 23 subjects (13 male, 10 female) with normal occlusions, taken at 13 (T1), 17 (T2) and 61 (T3) years of age. The following variables were measured in the maxillary anterior teeth using digital dental models: crown width/height proportion, anterior view width, crown angulation, gingival and incisal steps between central/lateral incisors and central incisors/canines. Interphase comparisons were evaluated using repeated measures analysis of variance followed by Tukey tests or Friedman tests. Sexual differences were evaluated using t tests (P < 0.05).

RESULTS

From 13 to 61 years of age, a decrease of crown width/height proportion (P = 0.008 and P =  < 0.001, for the lateral incisor and canines, respectively) and mesiodistal angulation (P =  < 0.001, P = 0.001 and P = 0.025 for the central incisor, lateral incisor and canines, respectively) of the maxillary anterior teeth were observed. The steps of the gingival margin and the incisal steps decreased with aging.

CONCLUSIONS

From adolescence to late adulthood, untreated individuals with normal occlusions demonstrated changes in the maxillary anterior teeth that may impair the smile esthetics and attractiveness.

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.

Observation and Assessment of the Parameters of Facial Esthetics in 6-year-old Children with Healthy Dentition

Aim

This study was conducted to observe and assess the dental and facial parameters of esthetics in children with healthy dentition and evaluate whether they are comparable to those of adults.

Materials and methods

An observational study included 70 children with ages ranging from 5 to 6 years who had come to the Department of Pediatric & Preventive Dentistry, Institute of Dental Studies & Technologies, Ghaziabad, Uttar Pradesh, India, with intact primary dentition. Standardized photographs of the children were taken and evaluated. Their facial and dental parameters were recorded and compared to that of those of adults.

Result

The relation of tooth and facial components was established, and it was found that they were not in the same proportion as those of adults.

Conclusion

The proportions of facial and dental parameters of esthetics of children at 6 years of age are different from those of adults.

Clinical significance

Since esthetic rehabilitation of primary teeth is becoming an important requisite of successful dental treatment, it is important to establish a standard guideline of dental and facial parameters for children for prosthetic rehabilitation.

How to cite this article

Potsangbam D, Agarwal N, Jabin Z, et al. Observation and Assessment of the Parameters of Facial Esthetics in 6-year-old Children with Healthy Dentition. Int J Clin Pediatr Dent 2023;16(4):608-611.

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.

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.

The perception of smile attractiveness to altered vertical position of maxillary anteriors by various groups

There is a gap in research about the differences in smile attractiveness. The problem the study addresses is how the vertical canine and incisor position affect smile attractiveness. The aim of this study was to assess the perception of the smile attractiveness between Saudi laypersons, orthodontists, non-orthodontist, and various dental students levels, and to determine how the canine and incisor vertical positions affect the attractiveness of smile. The study is a cross-sectional survey and was conducted at King Abdulaziz University, Jeddah, Saudi Arabia. Six groups of subjects participated in the study: Orthodontic residents (n = 31), prosthodontic, restorative, periodontics specialties residents specialties residents (n = 30), interns (n = 31), fifth year students (n = 41), 6th year students (n = 39), and laypeople (n = 39). Participants were asked to rate the attractiveness of a smile of a female subject photographed using a Minolta DiMage 7i digital camera. The image had been manipulated to produce 2 sets of images; 1 to modify the incisors and 1 to change the canines. The subjects were asked to choose the most and least attractive picture. For the best incisor positions, only the laypeople and prosthodontics liked the original picture, the rest liked +0.5 mm which accentuate the smile curve and make it follow the lower lip line. For the worst incisor position, all groups did not prefer the minus 1.5 reversed smile. For the best canine vertical position, all groups preferred the original position where canine was at the level of the incisal plane. For the worst canine position, they all disliked the minus 1.5 reversed smile. Results confirmed past findings that orthodontists are in general more critical about smile attractiveness than laypersons, but just like other dental specialists. The findings can be used in the esthetic dentistry field, but further research on the study population based on other dental design parameters remain necessary.

Esthetic and functional rehabilitation of peg-shaped maxillary lateral incisors: Practical recommendations

Peg-shaped maxillary lateral incisors cause many functional and esthetic major consequences in affected patients. Their esthetic and functional rehabilitations are often multidisciplinary, involving different clinical procedures like periodontal, orthodontic, or prosthodontic procedures. No exhaustive protocol has been established to improve their comprehensive management by general dentists or specialists. The aim of this article is to elaborate a simplified clinical protocol of complete management of peg-shaped maxillary lateral incisors by a multidisciplinary team (general practitioners, orthodontists, and prosthodontists). A clinical case of two peg-shaped maxillary lateral incisors completely rehabilitated with multidisciplinary approaches including orthodontic treatment and restoration by veneers and direct composite resin, according to the established protocol. Extraoral, intraoral, and smile clinical analysis are crucial to ensure optimal rehabilitation. Treatment results previsualization via wax-up and/or mock-up play a key role in the communication between practitioner and patient to help the latter make decision. These options also facilitate the achievement of a multidisciplinary approach by accurately estimating the number of dental movements and the type of restorations that are most suitable to the presenting clinical situation.

Proposed parameters of optimal central incisor positioning in orthodontic treatment planning: A systematic review

OBJECTIVE

Planning of incisal position is crucial for optimal orthodontic treatment outcomes due to its consequences on facial esthetics and occlusion. A systematic summary of the proposed parameters is presented.

METHODS

Studies on Google Scholar©, PubMed©, and Cochrane Library, providing quantitative information on optimal central incisor position were included.

RESULTS

Upper incisors supero-inferior position (4-5 mm to upper lip, 67-73 mm to axial plane through pupils), antero-posterior position (3-4 mm to Nasion-A, 3-6 mm to A-Pogonion, 9-12 mm to true vertical line, 5 mm to A-projection, 9-10 mm to coronal plane through pupils), bucco-lingual angulation (4-7° to occlusal plane perpendicular on models, 20-22° to Nasion-A, 57-58° to upper occlusal plane, 16-20° to coronal plane through pupils, 108-110° to anterior-posterior nasal spine), mesio-distal angulation (5° to occlusal plane perpendicular on models). Lower incisors supero-inferior position (41-48 mm to soft-tissue mandibular plane), antero-posterior position (3-4 mm to Nasion-B, 1-3 mm to A-Pogonion, 12-15 mm to true vertical line, 6-8 mm to coronal plane through pupils), bucco-lingual angulation (1-4° to occlusal plane perpendicular on models, 87-94° to mandibular plane, 68° to Frankfurt plane, 22-25° to Nasion-B, 105° to occlusal plane, 64° to lower occlusal plane, 21° to A-Pogonion), mesio-distal angulation (2° to occlusal plane perpendicular on models).

CONCLUSIONS

Although these findings can provide clinical guideline, they derive from heterogeneous studies in terms of subject characteristics and reference methods. Therefore, the optimal incisal position remains debatable.

Orthodontists' preferences regarding the difference of bracket bonding height between the maxillary incisors

Introduction:

The vertical position of orthodontic brackets in maxillary incisors may influence the incisal step between the anterior teeth and thereby interfere with the smile esthetics. Even so, esthetic standards have been modified over time and consistently required technical adjustments.

Objective:

This study analyzed orthodontists’ preferences regarding the difference of bracket bonding height between the maxillary central incisors (MCI) and maxillary lateral incisors (MLI), and further determined whether the orthodontist sex, age and time of specialization have association to their choices.

Methods:

This study collected data through an electronic form. Study participants analyzed a clinical case in which they indicated their preference for bracket bonding height. The placement height options ranged from 3.0 mm to 5.5 mm from the incisal edge, with 0.5-mm intervals, or at the clinical crown center (CCC). The difference in the bonding height between the MCI and MLI was analyzed, considering the formation of incisal steps between these teeth.

Results:

Participants indicated that the difference in bracket bonding height between the MCI and MLI should be as follows: 0 mm (3.9%); 0.5 mm (78.3%); 1 mm (7.6%); 1.5 mm (0.2%); and CCC (9.9%). There was no statistically significant correlation between the choice for bracket bonding height and sex, age and time since specialization.

Conclusion:

Most participating orthodontists choose the 0.5-mm difference in bracket placement height between the MCI and MLI. The variables sex, age and time since specialization did not influence this choice.

Does the presence of maxillary midline diastema influence the perception of dentofacial esthetics in video analysis?

OBJECTIVE

To evaluate the influence of a midline diastema on dentofacial esthetic perceptions of orthodontists, restorative dental specialists or prosthodontists, and laypersons in a frontal facial evaluation performed by means of video.

MATERIALS AND METHODS

Two individuals aged between 20 and 25 years, one of each gender, with presence of a midline diastema were selected. An acrylic resin mockup was made of the maxillary anterior region, simulating ideal conditions of smile esthetics. Four standardized frontal view videos of the complete face were filmed of each individual in the following situations: with the ideal smile (unchanged mockup) and with the presence of midline diastemas of 0.5, 1.0, and 1.5 mm created by the mockup. In all videos, the patient said a certain sentence and, at the end, simulated a posed smile. Dentofacial esthetic perceptions of all four videos of each individual were evaluated by 51 orthodontists, 51 restorative dental specialists or prosthodontists, and 51 laypersons by means of visual analog scales. Data were evaluated using analysis of variance and Tukey post hoc test, with the level of significance set at 5%.

RESULTS

The most attractive videos for all groups of examiners were those without diastema and with a diastema of 0.5 mm, for both the woman and the man. For a diastema of 1 mm or 1.5 mm, the dentofacial characteristics were considered unesthetic.

CONCLUSIONS

Diastemas equal to or greater than 1 mm negatively influence dentofacial esthetics in a frontal facial evaluation performed by means of video.

Accuracy of trial restorations from virtual planning: A comparison of two fabrication techniques

STATEMENT OF PROBLEM

Different technologies have been used to fabricate trial restorations. However, studies investigating the accuracy of trial restorations fabricated with different techniques in comparison with the initial 3-dimensional virtual design are lacking.

PURPOSE

The purpose of this clinical study was to evaluate completely digital workflows for managing the esthetic outcome through the production of trial restorations with 2 different technologies: stereolithography apparatus (SLA 3D) and computer-aided design and computer-aided manufacturing (CAD-CAM). The aim was to determine which of them provided trial restorations more similar to those of the 3D virtual design.

MATERIAL AND METHODS

Thirty participants who did not meet ideal esthetic proportions for the anterior maxillary teeth were enrolled. For each, 2 intraoral and extraoral frontal photographs and intraoral digital scans were made. The digital images were processed by using the Digital Smile System (DSS) software program to have a smile preview after the treatment. Virtual designs were matched with the surface tessellation language (STL) files from the intraoral scans and edited by exocad DentalCAD to create custom trial restorations using SLA 3D and CAD-CAM technologies. Two independent examiners measured the virtual restorations by using virtual calipers in the software program and then the trial restorations by using digital calipers. The measurements were carried out from the incisal edge to the gingival margin, mesial-distal widths of the central incisors, and the distance from the distal margins of maxillary right and left canines. The trial restorations were evaluated intraorally for fit. The participants approved the definitive treatment outcome after the evaluation. The normality of data was verified with the Shapiro-Wilk test, and the Friedman test for matched groups with the Bonferroni and Dunn tests for multiple comparisons were used (α=.05).

RESULTS

Comparing the 3D designs with the printed trial restorations, a significant increase was only found in the mesial-distal width of central incisors (P<.05), while the milled trial restorations showed a significant increase (P<.05) of all measurements except for the maxillary right and left canines. Comparing printed trial restorations with the milled ones, the only significant difference was found in height measures of maxillary right central incisor, with the milled trial restorations exhibiting higher values than the printed ones (P<.05). The printed trial restorations showed good clinical fit, and the milled restorations had poor clinical adaptation.

CONCLUSIONS

The accuracy of printed trial restorations was higher than that of milled trial restorations, except for the canine to canine width of maxillary anterior teeth. However, this difference did not compromise the fit of the printed trial restorations. The milled trial restorations had increased dimensions in comparison with the measurements made in 3D designs, and consequently, their clinical fit was compromised. SLA 3D- printing technology provided the best fit.

Perception of Smile Aesthetics of Patients with Anterior Malocclusions and Lips Influence: A Comparison of Dental Professionals’, Dental Students,’ and Laypersons’ Opinions

Objectives. The aim of the study was to evaluate the perception of smile aesthetics in patients with varying degrees of anterior crowding and spacing among dental specialists, dentists, dental students, and laypersons and to assess the effect of the lips position. Materials and Methods. Clinical photos of cases of anterior crowding (mild, moderate, and severe) and spacing (mild, moderate, and severe) with and without the associated lips were used. The images were evaluated by 250 persons including dental specialists, dentists, dental students, and laypersons using the rating scale method, (extremely unaesthetic to extremely aesthetic, 1 to 5, respectively). Nonparametric tests were used to analyse the data on SPSS version 24. Results. According to the 250 responses, the aesthetic perception of all severities of anterior crowding and mild and moderate spacing was found to be more aesthetic when displayed with the lips ( $p<0.05$ ). Additionally, the higher the level of dental education, the lower the aesthetic perception with and without the lips ( $p<0.05$ ). Conclusions. The lips play a significant role in improving the aesthetics of crowded anterior teeth and spaced anterior teeth. Dental educational level influences the aesthetic perception of anterior crowding and spacing. This may have an impact on treatment planning and need for orthodontic intervention.

Effects of gingival margin asymmetries on the smile esthetic perception of dental professionals and lay people

OBJECTIVE

To determine the effects of different gingival margin asymmetries of anterior tooth on the smile esthetic perceptions of dentists, prosthodontists, periodontists and lay people.

MATERIALS AND METHODS

A frontal close-up smile photo of a woman was used in this study. Image was digitally altered in order to create gingival margin asymmetries in left maxillary central, lateral incisors, and canines. Four stages of alterations were made in 0.5 mm increments. The final images were randomly assessed by 240 evaluators: 60 dentists, 60 prosthodontists, 60 periodontists, and 60 lay people. Questionnaire was carried out by a single researcher and each rater was asked to evaluate the attractiveness of the smile images by using the visual analog scale. Collected data were analyzed by using one-way ANOVA test with post hoc Scheffé test.

RESULTS

Smiles with 0.5 mm gingival margin asymmetries were found to be more esthetic, while 2 mm gingival asymmetries were less esthetic (P ˂ .001). Lay people's esthetic scores were higher than other groups in all degrees of asymmetries (P ˂ .001). Esthetic scores of canine teeth were higher than, lateral, and central teeth (P ˂ .001).

CONCLUSIONS

As the amount of asymmetries increased, esthetic scores decreased in all groups. Gingival margin asymmetries were less perceptible laterally.

CLINICAL SIGNIFICANCE

This study may help dental professionals to understand which gingival asymmetries are found by patients as esthetic or unesthetic and guides them in their dental treatment, especially in the aesthetic zone.

Perceptions and Preferences of Laypersons in the Management of Positional Plagiocephaly

BACKGROUND

Uncertain clinical evidence for treating positional plagiocephaly, especially with helmet therapy, creates difficulties in counseling parents of patients. This study investigates layperson perceptions and treatment preferences for positional plagiocephaly to provide patient-oriented evidence for management.

METHODS

Adult laypersons were recruited through crowdsourcing to view digitally-modified images of normal, mildly, moderately, or severely plagiocephalic infant heads. Participants provided demographic information and rated the infant's head shape and potential related social difficulties, likelihood of consulting a physician for treatment options, and likelihood of seeking helmeting treatment for the infant.

RESULTS

Nine hundred forty-five individuals participated in the study. Perception of head shape, prediction of future embarrassment and social difficulties, likelihood of seeking physician evaluation, likelihood of choosing helmet therapy, and willingness-to-pay for helmet therapy were pairwise-different between 4 plagiocephaly severities (corrected-P < 0.001 for all), except between normocephaly (n = 194) and mild (n = 334) plagiocephaly or between moderate (n = 203) and severe (n = 214) plagiocephaly. Younger respondents were more likely to consult a physician (uncorrected-P = 0.016) and choose helmet therapy (uncorrected-P = 0.004) for infants with normocephaly or mild plagiocephaly. Parents of children with physical disabilities were 6 times as likely as other participants to choose helmet therapy for mild plagiocephaly (corrected-P = 0.036).

CONCLUSIONS

Laypersons perceived moderate and severe plagiocephaly as equally abnormal and mild plagiocephaly as normal, consistent with their treatment preferences. Parents of physically disabled children were significantly more likely than other participants to choose helmet therapy. Our findings provide medical professionals with lay perspectives on positional plagiocephaly that may facilitate effective counseling of parents.

Does the presence of unilateral gingival recession on maxillary canines influence smile esthetics?

OBJECTIVE

The objective of this study was to determine orthodontists', periodontists', and laypersons' perception of smile esthetics, regarding the presence of different levels of gingival recession on the maxillary left canine.

MATERIAL AND METHODS

Two close-up smile images (frontal and oblique) of a white female were selected for this study. The images were digitally altered to create different levels of gingival recession on maxillary left canine, in 0.5-mm increments. They were randomly arranged into a photo album that was shown to 135 evaluators: 45 orthodontists, 45 periodontists, and 45 laypersons. Each evaluator was asked to rate the smile attractiveness, using to a visual analog scale. Data were analyzed statistically using ANOVA, Tukey's post-hoc test, and Student t-test.

RESULTS

According to the orthodontists and periodontists, all levels of recession were considered as unesthetic in both types of images. According to the laypersons, gingival recession > 1.5 mm in the frontal image and > 1.0 mm in the oblique image were considered unesthetic.

CONCLUSION

The results showed that the presence of unilateral gingival recession on maxillary canines may negatively influence smile attractiveness, depending on the evaluator type and the level of the recession.

Occlusal height difference between maxillary central and lateral incisors: should aesthetic perception influence bracket placement?

Background

Methods

Results

Conclusions

Does the vertical position of maxillary central incisors in men influence smile esthetics perception?

INTRODUCTION

The aim of this study was to investigate whether there is any influence on the perception of smile esthetics among orthodontists and laypersons, with regard to different vertical positions of the maxillary central incisors.

METHODS

Frontal smile photographs digitally altered at full-face view and close-up view of 2 adult men aged between 20 and 30 years were used. Six vertical positions of the central incisors were created, with changes of 0.5 mm. The images were randomly assembled in an album that was presented to 53 orthodontists and 53 laypersons, who evaluated the attractiveness of the images by using visual analog scales. Comparison among the images was performed using 1-way analysis of variance, with Tukey post-hoc test. To compare the distribution of the mean scores between the full-face and close-up smile views, and between orthodontists and laypersons, the Student t test was used. The level of significance was established at 5%.

RESULTS

The best evaluations presented the following: (a) the gingival margins of the central incisors corresponded to, or were up to, 1 mm below the line of the canine gingival margins, and (b) the incisal step between the central and lateral incisors was from 1.0 to 2.0 mm. The smiles considered least attractive showed (a) the central incisor gingival margins were 1.0 mm above or 1.5 mm below the canine gingival margins, and (b) no step, or a step of 2.5 mm, between the central and lateral incisors.

CONCLUSIONS

The results of this study suggested that, in men, slightly extruded central incisors were esthetically more attractive than intruded incisors.

Evaluation of objective and subjective treatment outcomes in orthodontic cases treated with extraction of a mandibular incisor

OBJECTIVES

To analyze changes in occlusal characteristics following mandibular incisor extractions (MIE), to determine the usefulness of wax setups in treatment planning MIE cases and to compare the pre- and posttreatment dental attractiveness between MIE cases and nonextraction (NE) controls.

MATERIALS AND METHODS

The Peer Assessment Rating (PAR) Index was used to score pre- and posttreatment dental casts of MIE cases (n = 14) and matched NE controls (n = 14). Occlusal characteristics were evaluated on diagnostic wax setups and posttreatment casts. Attractiveness of pre- and posttreatment cases judged on intraoral photographs of cases (n = 6) and controls (n = 6) were rated by 76 dental students and 10 laypeople using visual analogue scales (VAS).

RESULTS

The difference in PAR score reduction (%) between the MIE and NE groups was not significant. Between the wax setup and posttreatment casts, there were moderate correlations in overjet, overbite, and right canine classification. There was no significant difference in pre- and posttreatment change in VAS scores (%) for attractiveness between the MIE (49.8 ± 4.3 [S.E.]) and control groups (40.8 ± 4.3 [S.E.]). However, there was a significant difference (P = .000) between the observer groups.

CONCLUSIONS

There were no significant differences in the treatment outcomes of orthodontic cases treated with MIE or NE, indicating that MIE is a valid treatment option. A wax setup is moderately correlated with posttreatment results. Both laypeople and dental students rated posttreatment dental attractiveness higher than pretreatment in MIE and NE groups. Dental students tended to be more critical than laypeople in their ratings.

Influence of maxillary canine torque variations on the perception of smile esthetics among orthodontists and laypersons

OBJECTIVE

The purpose of this study was to determine the perception of smile esthetics among orthodontists and laypersons with respect to unilateral maxillary canine torque variations in a frontal smile analysis.

METHODS

Full face and close-up smile photographs of two subjects (1 man and 1 woman) were used. Both smiles displayed healthy maxillary anterior dentitions. The images were digitally altered to obtain a bilateral 0° torque in the maxillary canines. From this image, unilateral variations of the left canine were made with -15°, -10°, -5°, 0°, +5°, +10° and +15°. Final images were randomly assembled into an album that was given to 53 orthodontists and 53 laypersons. Each rater was asked to evaluate the attractiveness of the images using visual analog scales. Data collected were statistically analyzed with one-way analysis of variance with Tukey post-hoc test and the unpaired Student t test.

RESULTS

For orthodontists, most attractive smiles were those with 0°, -5° and -10°. For laypersons, most attractive smiles were those with 0°, -5°, -10°, -15° and + 5°. For both groups, the lowest scores were given for the smiles with +10° and +15° torque. When comparing the perceptions of the orthodontists and laypersons, they did not show statistical differences in most situations. Moreover, in general, there was no significant difference between the full-face and close-up assessments of the smiles.

CONCLUSIONS

The present findings indicated that smiles with unilateral palatal (negative values) maxillary canine torque variations were more tolerated than smiles with buccal crown torque (positive values) variations.

Does the presence of maxillary central incisor edge asymmetry influence the perception of dentofacial esthetics in video analysis?

OBJECTIVE

To investigate the influence of incisal edge asymmetry of the maxillary central incisors on dentofacial esthetics among orthodontists, prosthodontists, and laypersons using video analysis.

MATERIALS AND METHODS

Full-face films of a 52-year-old afro-descendant woman displaying various levels of incisal wear in the esthetic zone were captured. An acrylic resin mockup was made of the maxillary anterior region, enabling the reproduction of an attractive smile and restoring tooth wear. Four different levels of incisal asymmetry between the upper central incisors in 0.5 mm increments were prepared from this mockup. A film was made for each level of asymmetry (0.5, 1.0, 1.5, and 2.0) and one with no asymmetry, with the patient repeating a sentence, totaling five films. After a pilot study and sample calculation, the films were evaluated by 138 examiners: 46 orthodontists, 46 laypeople, and 46 prosthodontists. Each examiner evaluated the dentofacial esthetics of each film using visual analog scales. Data collected were statistically analyzed.

RESULTS

Highest scores were awarded to the film with no asymmetry between upper centrals and the one with 0.5 mm of asymmetry. The asymmetries of 1.5 mm and 2.0 mm had the lowest scores from all three groups.

CONCLUSIONS

The results of this video analysis indicate that asymmetries equal to or greater than 1.0 mm between the upper central incisors edges jeopardize dentofacial esthetics.

Do different vertical positions of maxillary central incisors influence smile esthetics perception?

INTRODUCTION:

The purpose of this study was to determine the perception of smile esthetics among orthodontists and layperson, with respect to different maxillary central incisors vertical positions in full-face and close-up smile analyses.

METHODS:

Frontal photographs of the smiles of two adult women were used. Images were altered to create a symmetrical image with the gingival margin levels of the maxillary canines matching the central incisors and a 1.0-mm central-to-lateral incisal step. Later, the images were altered in order to create six different central incisor vertical positions in 0.5-mm increments. The images were randomly assembled in an album, which was given to 114 judges, 57 orthodontists and 57 laypersons, who were asked to evaluate the attractiveness of the images using the visual analog scale. The data collected were statistically analyzed by means of 1-way analysis of variance with the Tukey post-hoc test and the Student t test.

RESULTS:

The highest rated smiles showed two notable characteristics: a) the central incisor gingival margins matched or were 0.5 mm below the line of the canine gingival margins and; b) the central-to-lateral incisal step was 1.0 to 1.5 mm. The worst smiles showed two notable characteristics: a) the central incisor gingival margins were 1.0 mm above or 1.5 mm below the canine gingival margins and; b) no step between the centrals and laterals or a 2.5-mm step.

CONCLUSION:

The vertical position of the maxillary central incisors significantly affected the perception of the smile esthetics, whereas slightly extruded central incisors were more esthetically preferred than intruded.

Smile esthetics: Impact of variations in the vertical and horizontal dimensions of the maxillary lateral incisors

OBJECTIVE

The purpose of this study was to determine the perception of trained dental professionals and laypersons toward the esthetic impact of variations in the vertical position, width, and gingival height of the maxillary lateral incisor.

MATERIALS AND METHODS

The present study analyzed the perspective of smile photographs by dental professionals such as "fifty orthodontics and fifty general dental practitioners (GDPs)" as well as fifty laypersons, consisting of an equal number of male and female participants. Photographs edited to depict alteration of golden proportion, incisal length, and gingival height of lateral incisor. SPSS software was used to analyze the data and determine the significant difference within all the participants, at 0.05% level (95% confidence interval).

RESULTS

There was no significant difference in ranking between the genders. Golden proportion of 62%-67% were ranked the highest by orthodontists, whereas GDPs and laypersons preferred 67%. Regarding gingival display, corrected height of -0.5 and -1 mm received highest ranking from all the three groups. In case of lateral incisal length, -0.5 mm was ranked highest by laypersons, in contrast to -1 mm by orthodontists and GDPs.

CONCLUSION

Specific differences were observed in the ranking of smile esthetics by health-care professionals and laypersons. Golden proportion of 62% and 67% were ranked the highest by orthodontists, whereas GDPs and laypersons preferred 67%. Corrected gingival height of -0.5 and -1 mm received highest ranking from all the three groups. In case of lateral incisal length, -0.5 mm was ranked highest by laypersons, in contrast to -1 mm by orthodontists and GDPs.

[Aesthetic perception of the vertical position of the incisal edges of the maxillary lateral incisors in the smile arch]

INTRODUCTION

The aim of this study is to assess the attractiveness in the smile arch of different vertical positions of the incisal edges of the maxillary lateral incisors.

MATERIAL AND METHODS

A frontal photograph of a Caucasian woman's smile was digitally modified to obtain an image with the incisal edges of the maxillary lateral incisors symmetrically tangent to the smile arch. These incisal edges were then moved vertically by 0.5 mm increments. The value was considered positive for an occlusal shift and negative for a gingival shift. Four other images were obtained by moving the incisal edges from +0.5 mm to -1.5 mm. The five images were rated on a visual analog scale by three groups of evaluators: orthodontists, dentists and laypersons. A statistical analysis was performed.

RESULTS

Laypersons preferred first lateral incisors tangent to the smile arch, second a +0.5 mm shift, and third a -0.5 mm shift. Orthodontists and dentists preferred first a -0.5 mm shift and second a null shift.

CONCLUSIONS

The aesthetic perception of the smile, as regard to the vertical relationships between the incisal edges of the anterior teeth, differs between laypersons and professionals but remains homogenous between orthodontists and dentists. The most consensual aesthetic situation, from both professionals' and laypersons' points of view, is the geometry in which the incisal edges of the maxillary lateral incisors are tangent to the smile arch.

Expert panels as a reference standard in orthodontic research: An assessment of published methods and reporting

INTRODUCTION

The aim of this study was to investigate the expert panel methodology applied in orthodontics and its reporting quality. Additionally, the relationship between the reporting quality and a range of variables was explored.

METHODS

PubMed was searched for orthodontic studies in which the final diagnosis or assessment was made by 2 or more experts published up to March 16, 2015. Reporting quality assessment was conducted using an established modified checklist. The relationship between potential predictors and the total score was assessed using univariable linear regression.

RESULTS

We identified 237 studies with a mean score of 9.97 (SD, 1.12) out of a maximum of 15. Critical information about panel methodology was missing in all studies. The panel composition differed substantially across studies, ranging from 2 to 646 panel members, with large variations in the expertise represented. Only 17 studies (7.2%) reported sample size calculations to justify the panel size. Panel members were partly blinded in 65 (27.4%) studies. Most studies failed to report which statistic was used to compute intrarater (65.8%) and interrater (66.2%) agreements. Journal type (nonorthodontic: β, 0.23; 95% CI, -0.07 to 0.54 compared with orthodontic), publication year (β, 0; 95% CI, -0.02 to 0.02 for each additional year), number of authors (1-3: β, 0.30; 95% CI, -0.13 to 0.74 compared with at least 6; 4-5: β, 0.18; 95% CI, -0.29 to 0.33 compared with at least 6), and number of centers involved (single: β, 0.20; 95% CI, -0.14 to 0.54 compared with multicenter) were not significant predictors of improved reporting. Studies published in Asia and Australia had significantly lower scores compared with those published in Europe (β, -0.54; 95% CI, -0.92 to -0.17).

CONCLUSIONS

Formal guidelines on methodology and reporting of studies involving expert panels are required.

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.

10 commandments of smile esthetics

The search for esthetic treatment has persisted in the routine of dental professionals. Following this trend, dental patients have sought treatment with the primary aim of improving smile esthetics. The aim of this article is to present a protocol to assess patient's smile: The 10 Commandments of smile esthetics.

Segmented arch or continuous arch technique? A rational approach

This study aims at revising the biomechanical principles of the segmented archwire technique as well as describing the clinical conditions in which the rational use of scientific biomechanics is essential to optimize orthodontic treatment and reduce the side effects produced by the straight wire technique.