Smile attractiveness in class III patients after orthodontic camouflage or orthognathic surgery

Comparative evaluation of periodontally accelerated osteogenic orthodontics (PAOO) versus traditional camouflage orthodontic treatment in adult patients with skeletal class III malocclusion

BACKGROUND

Existing literature supports the efficacy of PAOO in augmenting alveolar bone volume and facilitating orthodontic tooth movement. However, there is a paucity of literature addressing its application in the treatment of adults with skeletal Class III malocclusion. This retrospective clinical study aimed to compare the clinical efficacy of camouflage orthodontic treatment combined with and without PAOO in adult patients presenting with skeletal Class III malocclusion.

METHODS

A retrospective study was performed in 38 patients with mild to moderate skeletal Class III malocclusion who underwent orthodontic treatment. Patients were divided into two cohorts: the experimental group, which underwent the PAOO procedure combined with orthodontic treatment, and the control group, which received traditional camouflage orthodontic treatment alone. Radiographic assessments, including lateral cephalograms and cone-beam computed tomography (CBCT) scans, were conducted before treatment (T0) and after treatment (T1) to evaluate changes in maxillary incisor inclination, alveolar bone thickness, and various skeletal and soft tissue parameters.

RESULTS

The experimental group exhibited a significant reduction in the axial inclination of the maxillary incisors after treatment (P < 0.05; U1-PP, -4.97 ± 5.23°). The root apex of the maxillary incisors moved labially, and the A-point moved forward. In contrast, the control group demonstrated significant proclination of the maxillary incisors (P < 0.05; U1-PP, 6.80 ± 7.89°). The ANB assessments demonstrated significant improvements (P < 0.05; 3.03 ± 1.62°), with a significant difference between groups that favored the experimental group. Nasolabial angle and G Vert-Sn increased significantly only in the experimental group (P < 0.05; Nasolabial A, 9.47 ± 12.67°; G Vert-Sn, 2.19 ± 2.56 mm). Compared with T0, labial bone thickness significantly increased in the experimental group at T1, while it decreased significantly in the control group.

CONCLUSION

The integration of PAOO with orthodontic treatment appears to enhance labial alveolar bone augmentation and facilitate the labial movement of maxillary incisor roots in patients with skeletal Class III malocclusion. Concurrently, it results in significant improvements in patients' aesthetics of both soft and hard tissue profiles.

Comparison of smile attractiveness in cases with gummy smile treated with botulinum toxin and maxillary impaction surgery: A retrospective study

This study aimed to compare the smile's attractiveness in patients submitted to the treatment of gummy smiles with botulinum toxin or maxillary impaction surgery. The retrospective sample comprised 26 patients divided into two groups: Group 1 (BTX): 13 patients (12 females and 1 male) with a mean age of 28.06 years (s.d. = 6.09) and mean gingival exposure during smile of 5.18 mm (s.d. = 1.51) treated with botulinum toxin; Group 2 (SURGICAL): 13 patients (9 females and 4 males) with a mean age of 30.59 years (s.d. = 5.72) and mean gingival exposure during smile of 5.21 mm (s.d. = 1.55) treated with orthognathic maxillary impaction surgery. The group of evaluators comprised 317 participants, divided into 143 orthodontists (85 females and 58 males) with a mean age of 41.40 (s.d. = 9.30); 62 dentists (47 female and 15 male) with a mean age of 35.44 (s.d. = 10.44), and 112 lay people (74 female and 38 male) with a mean age of 46, 91 (s.d. = 10.11) in a questionnaire on Google Forms. Without knowing the therapy used, the evaluators assigned scores to the photographs of the posed smile taken before (T1) and after (T2) treatment. Intergroup comparison of smile attractiveness was performed using the t-independent, one-way ANOVA, and Tukey tests. There was a significant improvement in smile attractiveness with treatment in both groups; however, the improvement was significantly better in the surgical group than in the BTX group. Orthodontists rated smile attractiveness significantly higher than dentists and laypersons for the final phase of the BTX and surgical groups. There was a significant improvement in the smile attractiveness with botulinum toxin application and orthodontic-surgical treatment. However, orthognathic surgery promoted a greater improvement in smile attractiveness than the application of botulinum toxin.

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.

A novel machine learning model for class III surgery decision

PURPOSE

The primary purpose of this study was to develop a new machine learning model for the surgery/non-surgery decision in class III patients and evaluate the validity and reliability of this model.

METHODS

The sample consisted of 196 skeletal class III patients. All the cases were allocated randomly, 136 to the training set and the remaining 60 to the test set. Using the test set, the success rate of the artificial neural network model was estimated, along with a 95% confidence interval. To predict surgical cases, we trained a binary classifier using two different methods: random forest (RF) and logistic regression (LR).

RESULTS

Both the RF and the LR model showed high separability when classifying each patient for surgical or non-surgical treatment. RF achieved an area under the curve (AUC) of 0.9395 on the test set. 95% confidence intervals were computed by bootstrap sampling as lower bound = 0.7908 and higher bound = 0.9799. On the other hand, LR achieved an AUC of 0.937 on the test set. 95% confidence intervals were computed by bootstrap sampling as lower bound = 0.8467 and higher bound = 0.9812.

CONCLUSIONS

RF and LR machine learning models can be used to generate accurate and reliable algorithms to successfully classify patients up to 90%. The features selected by the algorithms coincide with the clinical features that we as clinicians weigh heavily when determining a treatment plan. This study further supports that overjet, Wits appraisal, lower incisor angulation, and Holdaway H angle can be used as strong predictors in assessing a patient's surgical needs.

Smile attractiveness in patients treated with or without 4 premolar extractions: A 36-year follow-up

INTRODUCTION

This study aimed to assess the smile attractiveness in patients treated with or without 4 premolar extractions at a 36-year follow-up.

METHODS

The sample comprised 52 patients with Class I and II malocclusion divided into 2 groups. Group 1 consisted of 15 patients treated without extractions (10 females and 5 males), with a mean pretreatment, posttreatment, and long-term posttreatment (T3) age of 13.2, 15.1, and 49.8 years, respectively. The mean treatment time was 1.9 years, and the mean long-term follow-up period was 34.7 years. Group 2 consisted of 37 patients (25 females and 12 males) treated with 4 premolar extractions, with a mean pretreatment, posttreatment, and long-term posttreatment age of 13.3, 15.7, and 53.6 years, respectively. The mean treatment time was 2.3 years, and the mean long-term follow-up period was 37.9 years. The mean retention time was 2 years for both groups. Frontal smiling photographs were obtained at long-term follow-up. Smile attractiveness was evaluated in an online questionnaire in which the evaluator could rate the smiling photographs with a 10-point scale. The randomly selected evaluator sample consisted of 62 laypeople, 33 dentists, and 89 orthodontists. Independent t tests, 1-way analysis of variance, and Tukey tests were used for intergroup comparisons at P <0.05.

RESULTS

The smile attractiveness on the long term was similar in the groups treated with 4 premolar extractions (4.70 ± 1.35) or without extractions (4.51 ± 1.46). Women and orthodontists were more critical in assessing smile attractiveness than men, dentists, and laypeople.

CONCLUSIONS

After long-term posttreatment, the smile attractiveness was similar in patients treated with 4 premolar extractions or without extractions.

Enhancing Surgical Outcomes via Three-Dimensional-Assisted Techniques Combined with Orthognathic Treatment: A Case Series Study of Skeletal Class III Malocclusions

(•) Orthognathic surgery is a necessary procedure for the correction of severe skeletal discrepancies, among which are skeletal Class III malocclusions. Currently, both conventional fixed braces and clear aligners can be used in orthognathic surgery. However, the use of clear aligners remains a little-chosen option. The present study aimed to evaluate the skeletal and aesthetic improvements in adults with Class III malocclusion after surgical treatment and compare the results achieved by fixed appliances versus clear aligners. The study sample included four patients (three males and one female, aged 18 to 34 years) with skeletal Class III malocclusion, three of whom underwent a bimaxillary surgery and one of whom underwent only a bilateral sagittal split osteotomy. Two patients were treated with fixed appliances and two with clear aligners. The pre- and post-surgical hard and soft tissue cephalometric measurements were performed and compared for each patient and between fixed appliances and clear aligners. One year after surgery, all patients showed an essential modification of the face’s middle and lower third with an increase in the convexity of the profile and the Wits index and a reduction in the FH^NB angle. No differences were noted between fixed appliances and aligners. Therefore, thanks to the 3D-assisted surgery associated with orthodontics, every participant achieved proper occlusal function and an improved facial aesthetics. In addition, the clear aligners can be considered a valid alternative for pre- and post-surgical orthodontic treatment.

[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.

Factors influencing the perception of profile beauty in Class III dental compensation: A comparative cross-sectional study according to three categories of assessors

INTRODUCTION

The main objective of this study was to evaluate the different factors influencing the perception of female profile facial beauty in Class III patients with protruded mandible that can be treated with orthodontic dental compensation: (1)severity of the protrusion, (2) the upper incisors inclination and (3) the presence of jawlines. The secondary objective was to determine if the rater's gender and profession played a role in the assessment of the preferred profile.

METHODS

A normal and smiling photographs of a female subject with normal facial and skeletal profile criteria were digitally manipulated to obtain 3 different mandibular sagittal positions: 0mm, +4mm and +8mm. Each position of the chin was evaluated with the presence or not of jawlines. In the smiling profiles, the same chin modifications were scored, and the maxillary incisor inclination was changed from 0 to +10 degrees with 5 degrees increments. A total of 320 raters (107 dentists, 103 orthodontists and 110 laypeople) scored the attractiveness of the different images using a Visual Analogue Scale. The limit of statistical significance was P<0.05. Generalized estimating equation (GEE) models were conducted to assess the predictors of variations in ratings within each set of photos, as well as the interactions of predictors where adjusted odds ratios (aOR) and their 95% confidence intervals were calculated and reported.

RESULTS

In the profiles without a smile, image +4mm chin (Class III treated by compensation) and image +8-mm mandible (Class III not treated) were selected as the most and least attractive images, respectively, by almost all groups with no difference. The presence of jawlines has a positive role in facial attractiveness. In the smiling profiles, all the examiners showed a preference for image +4-mm chin and a slight protrusion of maxillary incisors (+5 degrees). No significant difference was found between genders in this study.

CONCLUSIONS

Class III treated by compensation (+4mm) are more attractive than non-treated Class III (+8mm) by almost all groups with no difference. The presence of jawlines has a positive role in facial attractiveness. In the smiling profiles, all the examiners showed a preference for image +4-mm chin and a slight protrusion of maxillary incisors (+5 degrees). Orthodontists older than 50 years old are aware of the difficulty to treat a skeletal Class III and tend to accept it due to their long career experience. No significant difference was found between genders in this study.

The effect of orthodontic treatment on smile attractiveness: a systematic review

BACKGROUND

Smile attractiveness is a primary factor for patients to seek orthodontic treatment, however, there is yet no systematic evaluation of this topic in the literature.

OBJECTIVES

To assess the current evidence on the effect of orthodontic treatment on smile attractiveness.

SEARCH METHODS

Seven electronic databases (MEDLINE, Cochrane Library, Virtual Health Library, SCOPUS, Web of Science, Google Scholar and Embase) were searched on 14 September 2022.

SELECTION CRITERIA

Studies evaluating smile attractiveness before and after orthodontic treatment or only after completion of orthodontic treatment.

DATA COLLECTION AND ANALYSIS

Extracted data included study design and setting, sample size and demographics, malocclusion type, treatment modality and method for outcome assessment. Risk of bias was assessed with the ROBINS-I tool for non-randomised studies. Random-effects meta-analyses of mean differences and their 95% confidence intervals (CIs) were planned a priori.

METHODS

After elimination of duplicate studies, data extraction and risk of bias assessment according to the Cochrane guidelines, an evaluation of the overall evidence was performed. The included studies were evaluated based on the characteristics of their study and control groups and based on their main research question. Also, all outcome measures were standardized into a common assessment scale (0-100), in order to obtain more easily interpretable results.

RESULTS

Ten studies were included in this review, nine of which were assessed as being at serious risk of bias and one at moderate risk of bias. The large heterogeneity between the included studies did not allow for a meta-analysis. Orthodontic treatment has a moderately positive effect on smile attractiveness. When compared to no treatment, orthodontic treatment with premolar extractions improves smile attractiveness by 22%. Also, surgical correction of Class III cases increases smile attractiveness by 7.5% more than camouflage treatment. No other significant differences were shown between different types of treatment.

CONCLUSION

Based on the available data, orthodontic treatment seems to moderately improve the attractiveness of the smile. There is significant bias in the current literature assessing the effect of orthodontics on smile attractiveness; therefore, the results cannot be accepted with certainty.

Clear Aligners and Smart Eye Tracking Technology as a New Communication Strategy between Ethical and Legal Issues

Smart eye-tracking technology (SEET) that determines visual attention using smartphones can be used to determine the aesthetic perception of different types of clear aligners. Its value as a communication and comprehension tool, in addition to the ethical and legal concerns which it entails, can be assessed. One hundred subjects (50 F, 50 M; age range 15-70) were equally distributed in non-orthodontic (A) and orthodontic (B) groups. A smartphone-based SEET app assessed their knowledge of and opinions on aligners. Subjects evaluated images of smiles not wearing aligners, with/without attachments and with straight/scalloped gingival margins, as a guided calibration step which formed the image control group. Subsequently, the subjects rated the same smiles, this time wearing aligners (experimental images group). Questionnaire data and average values for each group of patients, and images relating to fixation times and overall star scores, were analyzed using these tests: chi-square, t-test, Mann-Whitney U, Spearman's rho, and Wilcoxon (p < 0.05). One-way ANOVA and related post-hoc tests were also applied. Orthodontic patients were found to be better informed than non-orthodontic patients. Aesthetic perception could be swayed by several factors. Attachments scored lower in aesthetic evaluation. Lips distracted attention from attachments and improved evaluations. Attachment-free aligners were better rated overall. A more thorough understanding as to the opinions, expectations and aesthetic perception of aligners can improve communication with patients. Mobile SEET is remarkably promising, although it does require a careful medicolegal risk-benefit assessments for responsible and professional use.

An Overview of Maxillofacial Approaches to Smile Design

The oral and maxillofacial surgeon (OMS) has the knowledge and skills to make drastic skeletal changes in favor of a more cosmetic smile. OMS can alter intraoral and extraoral soft tissues to make subtle or significant changes in facial cosmesis. This article provides an overview of the scope of the OMS in smile design. The authors provide a cursory review of pertinent gross and surgical facial anatomy, discuss the role of orthognathic surgery and rhinoplasty in smile cosmesis, and describe the fundamentals of common cosmetic procedures ranging from gingivoplasty to lip lift and lip augmentation and the use of neurotoxins.

Effects of sex, age, choice of surgical orthodontic treatment, and skeletal pattern on the psychological assessments of orthodontic patients

We aimed to examine the effects of sex, age, choice of surgical orthodontic treatment, and skeletal pattern on psychological assessment scores of orthodontic patients before edgewise treatment. They completed the State-Trait Anxiety Inventory (STAI), Beck Depression Inventory (BDI)-II, and the psychological domain of the World Health Organization Quality of Life 26 (Psych-QOL) for assessment of anxiety, depression, and body image, respectively. No significant effects on psychological assessment scores due to sex or age differences were found. Surgical orthodontic treatment patients and patients with skeletal Class III had significantly higher STAI-Trait and/or BDI-II scores and lower Psych-QOL score. Based on the linear mixed-effects model, the choice of surgical orthodontic treatment had a significant effect on the STAI-Trait, BDI-II, and Psych-QOL scores. No significant interaction effect was found between the choice of surgical orthodontic treatment and the skeletal pattern by ANB angle. Patients with skeletal Class I or III who chose surgical orthodontic treatment had higher STAI-Trait and/or BDI-II scores and/or lower body image score, respectively. These results suggest that patients who chose surgical orthodontic treatment, particularly those with skeletal Class I and III, may be more prone to experience anxiety and depression and have body image dissatisfaction.