Esthetic perception of clear aligner therapy attachments using eye-tracking technology

Accessories in clear aligner therapy: Laypeople's expectations for comfort and satisfaction

Background

This study explored the layperson's perception of comfort, satisfaction, and willingness to use various accessories in clear aligner therapy.

Methods

A total of 267 people analyzed standardized intraoral photographs of a female model in orthodontic treatment using: 1) only clear aligner (CA), the control group; 2) clear aligner+attachments (AT); 3) clear aligners+Cl II elastics (EL); 4) clear aligner+hybrid treatment with esthetic braces (HEB); 5) Clear aligner+hybrid treatment with metallic braces (HMB); 6) clear aligner+mini-implants (MI); 7) clear aligner+mini-implants and elastics for intrusion (MIE). In addition, a social media questionnaire was distributed to assess the willingness to undergo orthodontic treatment with various accessories.

Results

There was a significant difference between CA and all the other groups (P<0.001), with CA being considered more comfortable and providing greater satisfaction compared to other accessories. Moreover, AT showed a significant difference in reducing treatment time compared to other groups.

Conclusion

The CA was the most comfortable, exhibiting a higher satisfaction rate and a greater willingness to use it. The AT therapy was perceived as more comfortable and was associated with higher satisfaction and a greater likelihood of use, especially if it resulted in reduced treatment time. On the other hand, the participants reported that the HMB, MI, and MIE accessories were less comfortable.

The Use of Eye-Tracking Technology in Dento-Maxillofacial Esthetics: A Systematic Review

The use of eye-tracking technology in dental esthetics has gained popularity over the past decade because of its ability to assess observers' visual preferences in an objective manner. The goal of this study was to provide a comprehensive review of eye-tracking studies in dentistry, which could provide a reference for the rational and effective application of eye-tracking technology by dentists in the future. A comprehensive search of articles on eye tracking, published from January 1946 to June 2023, was conducted across several databases using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The major criterion for inclusion was that the study evaluated the use of eye-tracking technology in the field of dentistry. Two independent reviewers screened the eligible studies. A total of 67 articles were identified, 41 of which met our inclusion criteria. The most common application of eye tracking was the assessment of perceptions of changes in specific dental conditions among different classes of observers. Overall differences between groups (different classes of observers, different types of conditions) among different areas or regions of interest were analyzed. This systematic review demonstrated the utility of eye-tracking technology as a quantifiable objective assessment and emerging research tool for evaluating outcomes in several domains of dentistry.

Effect of attachment flash on clear aligner force delivery: an in vitro study

BACKGROUND

The introduction of auxiliaries such as composite attachment has improved the force delivery of clear aligner (CA) therapy. However, the placement of the attachment may give rise to a flash, defined as excess resin around the attachment which may affect CA force delivery. This in vitro study aims to determine the differences in the force generated by the attachment in the presence or absence of flash in CA.

MATERIALS AND METHODS

Tristar Trubalance aligner sheets were used to fabricate the CAs. Thirty-four resin models were 3D printed and 17 each, were bonded with ellipsoidal or rectangular attachments on maxillary right central incisors. Fuji Prescale pressure film was used to measure the force generated by the attachment of CA. The images of colour density produced on the films were processed using a calibrated pressure mapping system utilising image processing techniques and topographical force mapping to quantify the force. The force measurement process was repeated after the flash was removed from the attachment using tungsten-carbide bur on a slow-speed handpiece.

RESULTS

The intraclass correlation coefficient showed excellent reliability (ICC = 0.96, 95% CI = 0.92-0.98). The average mean force exerted by ellipsoidal attachments with flash was 8.05 ± 0.16 N, while 8.11 ± 0.18 N was without flash. As for rectangular attachments, the average mean force with flash was 8.48 ± 0.27 N, while 8.53 ± 0.13 N was without flash. Paired t-test revealed no statistically significant difference in the mean force exerted by CA in the presence or absence of flash for both ellipsoidal (p = 0.07) and rectangular attachments (p = 0.41). Rectangular attachments generated statistically significantly (p < 0.001) higher mean force than ellipsoidal attachments for flash and without flash.

CONCLUSION

Although rectangular attachment generated a significantly higher force than ellipsoidal attachment, the force generated by both attachments in the presence or absence of flash is similar (p > 0.05).

Aligner biomechanics: Where we are now and where we are heading for

Aligner orthodontics has gained significant popularity as an alternative to traditional braces because of its aesthetic appeal and comfort. The biomechanical principles that underlie aligner orthodontics play a crucial role in achieving successful outcomes. The biomechanics of aligner orthodontics revolve around controlled force application, tooth movement, and tissue response. Efficient biomechanics in aligner orthodontics involves consideration of attachment design and optimized force systems. Attachments are tooth-colored shapes bonded to teeth, aiding in torque, rotation, and extrusion movements. Optimized force systems ensure that forces are directed along the desired movement path, reducing unnecessary strain on surrounding tissues. Understanding and manipulating the biomechanics of aligner orthodontics is essential for orthodontists to achieve optimal treatment outcomes. This approach requires careful treatment planning, considering the mechanics required for each patient's specific malocclusion. As aligner orthodontics continues to evolve, advances in material science and treatment planning software contribute to refining biomechanical strategies, enhancing treatment efficiency, and expanding the scope of cases that can be successfully treated with aligners.

Effect of attachment configuration and trim line design on the force system of orthodontic aligners: A finite element study on the upper central incisor

OBJECTIVES

To use the finite element method (FEM) to investigate the effect of various attachment configurations and trimming line designs of orthodontic aligners on their biomechanical performance.

METHOD

A 3D upper jaw model was imported into 3D design software. The upper right central incisor tooth (Tooth 11) was made mobile, and its periodontal ligament (PDL) and bone structures were designed. Aligners were modelled with three distinct attachment configurations: No attachment, rectangular horizontal, rectangular vertical, and two trimming line designs; scalloped and straight extended, with a homogeneous thickness of 0.6 mm. These models were then imported into an FE software. Simulations were conducted for three different movements, including facial translation, distalization, and extrusion.

RESULTS

Forces were recorded at 1.3-2.6 N during facial translation, 1.4-5.9 N in distalization, and 0.0-2.0 N in extrusion. The straight extended trimming line consistently generated higher forces than the scalloped design. Attachments had no significant impact on force components during facial translation but were more effective in distalization and extrusion. The combination of a straight extended trimming line with horizontal attachments exhibited the least stresses at the apical third during distalization, and the highest stresses during extrusion, suggesting superior retention.

CONCLUSIONS

Rectangular attachments offer limited benefits in facial translation, but horizontal rectangular attachments can intensify load in distalization and are crucial for force generation in extrusion. Horizontal attachments are preferred over vertical options. Additionally, the straight extended trim line enhances control of tooth movement and can replace attachments in certain cases.

CLINICAL RELEVANCE

These findings provide biomechanical evidence and an optimal protocol to guide clinical practice in planning diverse teeth movements. The emphasis is on the influence of attachment utilization and the specific design of aligner trimming lines to enhance control over tooth movement.

Perception of color mismatch or conspicuous marginal adaptation in extraoral prostheses with eye-tracking

STATEMENT OF PROBLEM

Color matching and marginal integrity are major challenges when providing extraoral maxillofacial prostheses. Which of the color and marginal harmony features are more important for the extraoral prostheses to be inconspicuous is unclear. Studies on the perception of these prostheses with objective evaluation criteria are lacking.

PURPOSE

The purpose of this observational study was to investigate the significance of color mismatch and conspicuous marginal adaptation in the perception of extraoral maxillofacial prostheses using eye-tracking technology. The secondary aim was to evaluate the perception of extraoral maxillofacial prostheses with regard to the observers' sex.

MATERIAL AND METHODS

Twenty-seven face images, in 3 groups, representing well-fitting orbital prostheses with a color mismatch (IC), prostheses with a good color match but distinct marginal adaptation (IM), and symmetrical face images, were viewed for 5 seconds by 52 laypeople. Time to first fixation (TFF), fixation duration (FD), and fixation count (FC) at defined areas of interest were recorded and analyzed by an eye-tracking device. Because of the nested structure of data, a sex- and age-adjusted random intercept linear mixed effects model was used to assess the difference between IC, IM, and SI. Bonferroni corrected P values were used for pairwise comparisons. The difference between observers' sex was evaluated with random intercept mixed model by adjusting for age for each image. For repeated measurement analysis, the lm4, lmerTest, and emmeans libraries in R version 4.3.1 (R Foundation for Statistical Computing) were used (α=.05 for all tests).

RESULTS

Significant differences were found between the symmetrical image group and other study groups at the facial prosthesis region in all parameters (each P<.001). Observers first focused on the facial prostheses in IC (0.72 seconds) and in IM (0.789 seconds). Longer fixation durations, 1.909, 1.989 seconds for IC and IM (PIC<.001, PIM<.001), respectively, and a higher fixation count for IC (5.28) (P<.001) and for IM (5.45) (P<.001) were recorded on facial prostheses compared with other areas of interest. Women were more focused on the prosthesis than men in the IC and IM groups considering FD (PIC=.003, PIM<.001) and FC values (PIC=.016, PIM<.001, PSI<.001). Fixation duration for women and men was 2.097 seconds and 1.739 seconds in the IC group, 2.219 seconds and 1.78 seconds in the IM group, and 1.364 seconds and 1.222 seconds in the SI group, respectively.

CONCLUSIONS

Since the color mismatch and distinct marginal adaptation of maxillofacial prostheses were recognized using eye-tracking technology, both features appeared to be equally significant to be considered in fabrication procedures.

Orthodontic aligners: between passion and science

INTRODUCTION

The benefits and safety of using orthodontic aligners have been reported more by clinical experience and expert opinion than by scientific evidence. Another important aspect is that aligners are constantly evolving. It is important to obtain evidence that allows for new updates in manufacturing technology, in the development of new movement planning protocols, in the incorporation and design of attachments, and in the aid of skeletal anchorage.

METHODS

Evidence retrieved from six electronic databases (CINAHL, MEDLINE, EMBASE, Psych Info, the Cochrane Library and the Joanna Briggs Library) is presented by means of questions and answers.

CONCLUSIONS

There is evidence that the aligners presented different levels of difficulty in performing each type of movement, with rotational and vertical movements being the most difficult to perform. Regarding perception of pain due to tooth movement, it seems to have less impact at the beginning of treatment; but dealing with more phonoarticulatory changes seems to require more treatment time in more complex cases. Aligners do not prevent the occurrence of root resorption, although the incidence and severity of resorption may be reduced, making oral hygiene easier and accepting the risk of white spots, caries and periodontal disease. Given the conflicting evidence, the release of bisphenol-A from the aligner cannot be denied. Solutions must be found to reduce the environmental impact of aligners disposal. There is an urgent need for well-designed randomized controlled trials.

Effect of clear aligner attachment design on extrusion of maxillary lateral incisors: A multicenter, single-blind randomized clinical trial

INTRODUCTION

Extrusion of maxillary lateral incisors during aligner treatment is a difficult movement to achieve accurately. Despite recommendations regarding attachment design, few studies and no prospective trials compare predictability among attachments. This study aimed to compare the efficacy between optimized and horizontal attachment designs for achieving maxillary lateral incisor extrusion during clear aligner treatment.

METHODS

The study included maxillary lateral incisors in 3 orthodontic practices requiring at least 0.3 mm of extrusion during the first series of 20-25 aligners in patients aged ≥16 years who were scheduled to begin clear aligner treatment (Invisalign; Align Technology, San Jose, Calif). Teeth were randomly assigned to receive optimized (O), rectangular horizontal nonbeveled (H), rectangular horizontal incisally-beveled (HIB), or rectangular horizontal gingivally-beveled (HGB) attachments. After the first series, a blinded evaluator measured extrusion using superimpositions with initial and predicted models. Linear models determined the difference in the predicted extrusion percentage achieved on the basis of attachment design. Other covariates were patient age, sex, number of trays, and self-reported compliance.

RESULTS

Forty patients (74 teeth) were enrolled, and 38 patients (71 teeth) completed the study. Intraexaminer and interexaminer reliability for extrusion measurements was high (intraclass correlation coefficient, 0.985 and 0.991, respectively). The achieved extrusion was significantly less than predicted (mean, 73%; P <0.0001). The average achieved extrusion was 62%, 79%, 78%, and 78% for O, H, HIB, and HGB attachments, respectively, with H significantly more effective than O (P = 0.0403). Horizontal attachments (H, HIB, and HGB combined) were significantly more effective than O attachments (P = 0.0060), with an average difference in achieved extrusion of 14% of the predicted amount (95% confidence interval, 4-23; estimated 76% vs 62%). Horizontal attachments were an estimated 22% more effective than O attachments for extruding maxillary lateral incisors.

CONCLUSIONS

Horizontal attachments are more effective than O attachments for predicted maxillary lateral incisor extrusion between 0.3 and 2.5 mm. The 3 horizontal attachment designs evaluated performed similarly for achieving predicted extrusion.

TRIAL REGISTRATION

This randomized clinical trial was registered and reported at clinicaltrials.gov (NCT04968353).

PROTOCOL

The protocol was not published before trial commencement.

FUNDING

This study was funded in part by the Alexander Fellowship of the Virginia Commonwealth University School of Dentistry, the Southern Association of Orthodontists, and the Virginia Orthodontic Education and Research Foundation. No funding source influenced the study design, the collection, analysis or interpretation of data, writing of the report, or the decision to submit the article for publication.

Does the composite attachment of clear aligners compromise the effectiveness of dental bleaching? An in vitro study

INTRODUCTION

This study aimed to evaluate the effectiveness of dental bleaching with hydrogen peroxide 35% on the surface below the attachments.

METHODS

Twenty-four blocks of bovine incisors were equally divided into 2 groups. The control group comprises the enamel surface free of attachments, whereas the attachment group comprises the enamel surface with attachment. Initial staining of samples was performed with black tea for 7 days; then, an attachment was made in the attachment group with Z250 resin and new staining for another 7 days in all samples. After staining, in-office bleaching was performed in both groups, and the attachments from the attachment group were removed. Color reading was performed with a spectrophotometer at all stages: initial (baseline), after 7 days of staining, after 14 days of staining, after immediate bleaching, and after 24 hours of bleaching. The color difference was calculated, and data analysis was performed using the t test for intergroup analysis.

RESULTS

The results showed effective bleaching in both groups; however, there was a statistically significant difference in color change between them 24 hours after bleaching.

CONCLUSION

It was concluded that the presence of attachment did not impair the action of the bleaching agent on the tooth surface.

Orthodontics social media, perceptions of science- and non-science-based posts among orthodontists, dentists, students and laypeople

Worldwide, social media is gaining popularity year after year. In Brazil, by 2027, there will be more than 188 million users of social media sites, against 165 million in 2022, therefore, the usage of general population and health care professionals, including orthodontists, is increasing. Differently from scientific journals that undergo a rigorous peer review process prior to publication, the same level of demand is not found on social media. Hence, this study aimed to assess whether orthodontists can recognize scientifically based and non-science-based posts and if their perceptions are different from general opinion (laypeople), dentistry students, and dentists (non-orthodontists). The posts were created using the search tool on Instagram with the hashtags #clearaligners #acceledent #selfligatingbraces and #propelorthodontics, four scientific based posts and four without or with low scientific evidence were selected and evaluated through a virtual questionnaire in the QUALTRICS platform by 385 people, (175 laypeople, 102 dentists, 58 dentistry students, and 50 orthodontists) using a visual analogue scale (VAS). In addition, four questions were asked. ANOVA (Adjusted Bonferroni correction) and Pearson's chi-squared, and Student T tests were applied to identify statistical differences. Significant difference was found only for posts with no scientific evidence between orthodontist's group when comparing with laypeople (p < 0.001) for the #selfligatingbraces, and the #propelorthodontics for the group orthodontists when compared with laypeople (p = 0.031) and dentists (p = 0.033). Instagram was the favorite social media where most of the participants spend more than 3 h. Of the participants, 97% used social media to keep informed and read the news. Almost half of the respondents search for orthodontics services on social media. Orthodontists were able to perceive differences in only two posts from the general perception (laypeople) regarding non- or low-scientific-evidence posts.

Clear Aligner Therapy: Up to date review article

The advantages of Clear Aligners Therapy (CAT) include the braces being virtually invisible, comfortable to wear, and removable for eating and brushing; that way, CAT can be used to treat a wide range of orthodontic issues. In 1999, the company Align Technology introduced the frst commercial clear aligner system called Invisalign. The Invisalign system was initially only available to orthodontists, but later became available to general dentists as well. The system quickly gained popularity among patients who were looking for a more discreet and comfortable alternative to traditional braces. In 2000, Align Technology received FDA clearance for the Invisalign system, which further increased its popularity. The biomechanics of clear aligners involve the use of custom-made tooth aligners that are specifcally shaped to guide teeth into desired positions. These aligners are typically made from flexible materials such as polyurethane or ethylene vinyl acetate and are adjusted to apply the necessary forces for tooth movement. Attachment devices, such as power ridges or buttons, are often used to enhance or assist in specifc tooth movements and for retention of the aligner. The use of attachments allows for the exertion of desired force on the teeth, which is crucial for the success of Clear Aligner Therapy. CAT should be used if patients are concerned about the esthetic appearances of their teeth-for example, actors and other individuals that rely on their appearances in public in a professional context-and if the misalignment is not severe, so that clear aligners can still work. One should not use CAT in cases of severe crowding or spacing issues that require extractions. If the patient has complex jaw discrepancies or skeletal issues or if teeth need to be moved extensively in multiple directions, CAT is likely not going to be strong enough. In conclusion, Clear Aligner Therapy is a safe, effective, and convenient orthodontic treatment option that offers patients a virtually invisible way to achieve a straighter, more beautiful smile. With continued advancements in technology and a growing body of research supporting its effectiveness, the future of Clear Aligner Therapy looks bright.

Perceived esthetics and value of clear aligner therapy systems: A survey among dental school instructors and undergraduate students

OBJECTIVE

To investigate the attractiveness, acceptability, visibility and willingness-to-pay for clear aligner therapy (CAT) systems in first-year and final-year dental students and instructors.

METHODS

A questionnaire designed to collect information regarding esthetic preferences and intentions related to seven CAT systems was handed out to 120 undergraduate students and instructors at the Academic Centre for Dentistry Amsterdam (ACTA). Proportional odds models and population average generalized estimating equation models were used to examine potential association between participant characteristics, esthetic perceptions and CAT systems.

RESULTS

Overall, the examined CAT systems received favorable esthetic ratings. Expertise status was significantly associated with willingness-to-pay additionally for CAT, compared to fixed orthodontic appliances. There was no association between sex, previous orthodontic treatment history, satisfaction with own dental appearance and potential interest in treatment and aligner visibility and willingness-to-pay. CAT system was significantly associated with the perceived aligner visibility, acceptability and attractiveness by students and instructors.

CONCLUSIONS

CAT systems were considered to a great extent attractive and acceptable for future treatment by dental school instructors and students. Willingness-to-pay for CAT systems was significantly associated with expertise status, with instructors appearing more reluctant to pay for CAT.

Attachments for the Orthodontic Aligner Treatment-State of the Art-A Comprehensive Systematic Review

BACKGROUND

In recent years the burden of aligner treatment has been growing. However, the sole use of aligners is characterized by limitations; thus attachments are bonded to the teeth to improve aligner retention and tooth movement. Nevertheless, it is often still a challenge to clinically achieve the planned movement. Thus, the aim of this study is to discuss the evidence of the shape, placement and bonding of composite attachments.

METHODS

A query was carried out in six databases on 10 December 2022 using the search string ("orthodontics" OR "malocclusion" OR "Tooth movement techniques AND ("aligner*" OR "thermoformed splints" OR "invisible splint*" AND ("attachment*" OR "accessor*" OR "auxill*" AND "position*").

RESULTS

There were 209 potential articles identified. Finally, twenty-six articles were included. Four referred to attachment bonding, and twenty-two comprised the influence of composite attachment on movement efficacy. Quality assessment tools were used according to the study type.

CONCLUSIONS

The use of attachments significantly improves the expression of orthodontic movement and aligner retention. It is possible to indicate sites on the teeth where attachments have a better effect on tooth movement and to assess which attachments facilitate movement. The research received no external funding. The PROSPERO database number is CRD42022383276.

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.

Force profile assessment of direct-printed aligners versus thermoformed aligners and the effects of non-engaged surface patterns

Background

The purpose of the study was to measure the forces delivered by direct-printed aligners (DPA) in the vertical dimension and compare the force profile with traditional thermoformed aligners (TFA) and to investigate the impact of non-engaged surface patterns to the properties of DPA and TFA.

Methods

A force-measuring appliance was fabricated capable of displacing the aligner in 0.10 mm increments and measuring the resultant force. Polyethylene terephthalate glycol (ATMOS 0.030″ American Orthodontics) and TC-85DAC resin (Graphy Inc) were used to create TFA and DPA, respectively. Aligners were temperature-controlled prior to and during testing to simulate the oral environment. The resultant forces from displacements ranging from 0.10 to 0.30 mm were measured.

Results

At intraoral temperatures, DPA demonstrated significantly less force than TFA. TFA demonstrated a substantial statistically significant increase in force with each 0.10 mm increase in vertical displacement. DPA demonstrated a much more consistent force profile across the range of displacements. The effects of surface patterns in both DPA and TFA were generally a decrease in force. Statistical significance of surface patterns was detected for TFA at displacements of 0.30 mm and greater and significant for DPA only at a displacement of 0.10 mm. Surface patterns in both DPA and the TFA did not show any statistical difference when assessing force proprieties.

Conclusions

Forces delivered by aligners in the vertical dimension by DPA are more consistent and of lower magnitude than those of TFA aligners. Surface patterns were not capable of altering the force properties of both DPA and TFA.

Public perception of Invisalign® clear aligner treatment: A cross-sectional survey-based study

Objectives:

The demand for clear aligner treatment has increased in recent years. Thus, this study investigated public knowledge regarding Invisalign clear aligner treatment.

Material and Methods:

A web-based survey was administered through different social media platforms covering different aspects of Invisalign treatment, namely: Treatment efficiency, patient discomfort, appliance esthetic attractiveness, oral hygiene maintenance, and treatment aesthetic results. Participants were also asked to outline their perception of Invisalign treatment cost. A Likert-type scale was used to rank the participant responses. Data were analyzed with the Chi-square test and Bonferroni correction for multiple comparisons.

Results:

Out of 934 eligible adult participants, 19.6% were aware of Invisalign. Most of the Invisalign-familiar respondents were unaware of its cost (27.9%) but agree it is generally better (49.7%), requires fewer visits (38.2%), results in shorter treatment duration (39.4%) and reduced teeth discomfort (35%), more esthetically attractive (64%), yields easier oral hygiene maintenance (55.2%), and produces superior esthetic results (43.7%) than traditional braces. In addition, males and average-income participants were more likely to believe that Invisalign treatment produces superior esthetic results than traditional braces (P = 0.0002 and P = 0.002, respectively). Average-income participants also believed that Invisalign treatment was generally better (P < 0.0001). While participants in the age-range 55–64 years strongly believe, it is cheaper (P < 0.0001) than traditional braces.

Conclusion:

This study highlighted the lack of public knowledge about Invisalign treatment. The results also indicated the importance of ensuring public access to reliable information backed up by high-quality evidence.

Predicting patient experience of Invisalign treatment: An analysis using artificial neural network

Objective

Poor experience with Invisalign treatment affects patient compliance and, thus, treatment outcome. Knowing the potential discomfort level in advance can help orthodontists better prepare the patient to overcome the difficult stage. This study aimed to construct artificial neural networks (ANNs) to predict patient experience in the early stages of Invisalign treatment.

Methods

In total, 196 patients were enrolled. Data collection included questionnaires on pain, anxiety, and quality of life (QoL). A four-layer fully connected multilayer perception with three backpropagations was constructed to predict patient experience of the treatment. The input data comprised 17 clinical features. The partial derivative method was used to calculate the relative contributions of each input in the ANNs.

Results

The predictive success rates for pain, anxiety, and QoL were 87.7%, 93.4%, and 92.4%, respectively. ANNs for predicting pain, anxiety, and QoL yielded areas under the curve of 0.963, 0.992, and 0.982, respectively. The number of teeth with lingual attachments was the most important factor affecting the outcome of negative experience, followed by the number of lingual buttons and upper incisors with attachments.

Conclusions

The constructed ANNs in this preliminary study show good accuracy in predicting patient experience (i.e., pain, anxiety, and QoL) of Invisalign treatment. Artificial intelligence system developed for predicting patient comfort has potential for clinical application to enhance patient compliance.

Clear aligners with differentiated thickness and without attachments - A case report

Background

Most clear aligner systems use straight or scalloped gingival margin aligners that are replaced weekly and that mainly use attachments to guide many movements. Yet in the literature some studies show the effectiveness of the aligner margin extended beyond the gingival margin, and divots instead of attachments and the biological advantage given by the use of aligners with differentiated thickness.

Material and Methods

A female patient (23 years old) with a pronounced proclination of the upper and lower incisors and moderate crowding who was treated with aligners weekly replaced with differentiated thickness, divots, no attachments and a straight margin beyond the gingival margin.

Results

The therapy was carried out in 5 months and did not need any refinements. A total of 40 aligners were used (20 with soft thickness and 20 with hard thickness for each arch).

Conclusions

Invisible aligners without attachments and with other therapeutic strategies such as divots and differentiated thickness are a valid alternative to traditional aligners that cannot be ignored. Key words:Orthodontics, clear aligners, appliances design.

The influence of malocclusion on social aspects in adults: study via eye tracking technology and questionnaire

BACKGROUND

Smile esthetics has a strong influence on perception, attractiveness, and personal characteristics. It is unknown how malocclusions may influence the appearance of the individual's smile. This study aimed to investigate whether malocclusion affects the visual perception of esthetics, age, employability, honesty, intelligence and to meet its obligation in time in middle-aged adults. Facial frontal smiling photographs of a male and a female middle-aged adult with 3 different malocclusions were shown to and evaluated by 90 laypeople (non-dentists), divided into groups: young adults (14-44 years), middle-aged adults (45-59 years), and elders (over 60 years). The index of treatment need (IOTN) was used, and IOTN 1, 5, and 8 images were created in Photoshop using the male and female photographs. In total, 6 photographs were evaluated, 3 areas of interest (AOI)-eyes, nose, and mouth-were created for statistical comparison. The Ogama and Eye Tribe tracker were used in conjunction to measure eye tracking. A visual analog scale (VAS) was employed with a questionnaire surveying individuals' perception of age, employability, honesty, intelligence, and ability to meet obligations. Kruskal-Wallis, one-way analysis of variance, Pearson's-chi-squared, and Pearson correlation test were applied.

RESULTS

No statistical difference was found in complete fixation time and time until the first fixation for each AOI for eye-tracking. VAS showed statistical differences in the male and female IOTN 1 images when compared with the IOTN 5 and 8 for both models, and there was no difference between genders in the IOTN 1. As the perceived age of the model increased, the chances of getting hired decreased. Employability, honesty, intelligence, and ability to meet obligations showed higher values for IOTN 1. There were significant differences between age ranges; perception of intelligence in the female IOTN 1 model (p = 0.002) and IOTN 8 model (p < 0.001) and honesty between young adults and middle-aged adults in the male IOTN 1 and 8 images (p < 0.001).

CONCLUSIONS

There was a difference between age groups in the perception of honesty and intelligence. A well-balanced and attractive was perceived as more youthful and attractive in both genders and may increase the chance of being selected for a job interview or being hired.

Appropriate orthodontic appliances during the COVID-19 pandemic: A scoping review

INTRODUCTION

The esoteric Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2) infection or COVID-19 has been an unusual plummet in dental/orthodontic practice. Based on current recommendations for various amendments in an orthodontic practice, this scoping review aims to identify orthodontic appliances that are most appropriate to us during this on-going pandemic.

METHODS

Electronic databases (PubMed, Scopus, Web of Science, Science Direct, and Google Scholar) were searched up until August 11, 2020. Full-text articles in English with keywords "COVID-19 and Orthodontics" and related search terms were included.

RESULTS

Out of 17 retracted articles, only 4 articles were found to be brief the choice for orthodontic appliances in pandemic times speculating clear aligner therapy (CAT) to be a pragmatic solution. The remaining articles were also thoroughly studied and the new norms set by the pandemic were determined. Criteria for orthodontic appliance selection included careful patient screening and collection of records, minimal physical visits, efficient use of technology, virtual consultations but the use of PPE for physical appointments; and lesser AGPs with a lesser risk of airborne transmission.

CONCLUSIONS

Subject to regional demands, CAT can be considered as the relatively safer modality-predictable and effective apposite to fixed orthodontic appliances in these unprecedented times.

Accelerated orthodontics: Getting ahead of ourselves?

There is disagreement as to what constitutes an acceptable duration for orthodontic treatment but seeming unanimity that acceleration is required. This contention has spawned a range of surgical and non-surgical adjuncts designed to accelerate orthodontic tooth movement, geared at reducing overall treatment times while maintaining optimal occlusal results. Largely, however, marketed non-surgical adjuncts and involved surgical procedures have shown equivocal effectiveness in reducing treatment times. Notwithstanding this, a range of key treatment decisions and approaches may have a more potent effect. While external solutions may offer alluring possibilities, perhaps, more mundane realities including refinement of orthodontic planning and decision-making with efficiency and process, as well as final outcome, in mind continue to offer the most accessible and influential means of improving orthodontic efficiency?

Space closure using aligners

INTRODUCTION

Due to the search for more aesthetic and comfortable alternatives to perform orthodontic treatments and to the great technological development, orthodontic aligners have assumed great importance. More and more complex treatments have been carried out with these appliances without, however, having all aspects involved in their use being studied in depth. Its biomechanical planning requires different approaches than those used in fixed orthodontics, as the force systems involved in movements, responses and side effects are distinct, and the professional must be prepared when opting for the technique.

OBJECTIVE

The objective of this article is to perform an evaluation of the force systems created on the space closure with aligners, its characteristics, and problems, as well as make some suggestions to overcome the difficulties inherent to its use.

CONCLUSION

Space closure with aligners is possible, but depends on the correct selection of the patient, in addition to requiring the proper planning of the applied forces. The use of auxiliary resources and overcorrections to address the deficiencies of the aligner systems should always be considered. Digital planning should be used as a map of the force systems that will be applied, and not just as a marketing tool, keeping in mind that determining the objectives and the way to achieve them is the responsibility of the orthodontist, and that treatment plans must be individualized for each situation, following appropriate biomechanical precepts.