Does crown, root, and bone visualization in a clear aligner virtual setup impact treatment decisions?

INTRODUCTION: Clear aligner technology based on a machine learning algorithm is currently available for orthodontic treatment. Treatment planning on the basis of 3-dimensional crown, root, and bone imaging is claimed to provide accurate diagnosis and better treatment outcomes for adult patients with complex needs. This study aimed to answer the following questions: (1) would practitioners modify their original treatment plan once provided with the crown, root, and bone view? and (2) does practitioner satisfaction regarding treatment outcomes change once the crown, root, and bone view is provided? METHODS: An online questionnaire was emailed to members of the American Association of Orthodontists (n = 2300) and the Virginia Orthodontic Education and Research Foundation (n = 211). The survey consisted of videos of 4 patients shown in 2 presentations: crown-only and crown, root, and bone views, generated by artificial intelligence-driven treatment planning software (3D Predict aligner system; 3D Predict, New York, NY). Respondents were asked to answer treatment-related questions and rate the treatment outcomes using a visual analog scale. Statistical analyses were completed to determine the significance of crown, root, and bone view on treatment planning with clear aligners. RESULTS: A total of 70 orthodontists participated in the survey. There were significant differences in responses when viewing patients in crown-only and crown, root, and bone presentations. Across the 4 patients, 33%-43% of practitioners changed their sentiment toward the treatment plan (P <0.001). When rating satisfaction on the 100-point scale, average ratings changed by 10.6 to 21.0 points; both increases and decreases in satisfaction were seen across the patients (P <0.001). CONCLUSIONS: When given 3-dimensional information on the position of a patient's crowns, root, and bone coverage, orthodontists are likely to change their clear aligner treatment plan. This study showed that a confirmation of dehiscence and fenestrations using the root and bone view resulted in practitioner dissatisfaction despite an initial satisfaction with the crown-only view.

Laryngeal cartilage calcifications on lateral cephalometric radiographs.

The aim of this study was to determine the influence of age and gender on the incidence of calcification in laryngeal cartilage diagnosed on lateral cephalometric radiographs routinely taken for orthodontic diagnosis. The lateral cephalometric radiographs of 957 patients who met the study criteria were analyzed from among the 1000 lateral radiographs originally collected. The images were evaluated independently by two investigators. Given the dichotomous dependent variable (calcification or no calcification), a mixed logistic regression model was used to test how age and gender affected calcification. The effect of age and gender reliably determined the likelihood of laryngeal cartilage calcification. The greatest differences in the degree of calcification by gender were found at ages 20-25 years. The degree of calcification increased with age, reaching 100% in women at age 30 and in men at age 50. In women, the degree of calcification was higher than in men from the age of 13 years and levelled off at the age of 50 years. The interrater agreement was strong k = 0.97, z = 30.0, p < .001. Calcification can be detected by orthodontists trained in lateral cephalogram analysis and can be used as a screening or diagnostic tool to detect calcified areas in the larynx.

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.

Clear aligner therapy in the mixed dentition: Indications and practitioner perspectives.

INTRODUCTION: This study evaluated current trends and perspectives among orthodontists regarding clear aligner therapy in the mixed dentition (CAMD), including insights into perceived indications, compliance, oral hygiene, and other factors. METHODS: An original, 22-item survey was mailed to a randomized, nationally representative sample of practicing orthodontists (n = 800) and a specific, randomized subsample of high-aligner-prescribing orthodontists (n = 200). Questions assessed respondents' demographic information, experience with clear aligner therapy, and perceived advantages and disadvantages of CAMD compared with fixed appliances (FAs). Responses were compared using McNemar's chi-square and paired t tests to assess CAMD vs FAs. RESULTS: One thousand orthodontists were surveyed, and 181 (18.1%) responded over 12 weeks. CAMD use was less common than mixed dentition FAs, but most respondents predicted an increase in their future CAMD use (57.9%). Among respondents using CAMD, the number of patients with mixed dentition treated with clear aligners was significantly lower than the number of total patients with clear aligners (23.7% vs 43.8%; P <0.0001). Fewer respondents considered skeletal expansion, growth modification, sagittal correction, and habit cessation feasible indications for CAMD compared with FAs (P <0.0001). Perceived compliance was similar for CAMD and FAs (P = 0.5841), but perceived oral hygiene was significantly better with CAMD (P <0.0001). CONCLUSIONS: CAMD is an increasingly common treatment modality for children. Most surveyed orthodontists reported limited indications for CAMD compared with FAs but perceived noticeable benefits for oral hygiene with CAMD.

Adaptations in orthodontics for current and future coronavirus disease 2019 best practices.

INTRODUCTION: This study aimed to determine adaptations orthodontists made during the coronavirus disease 2019 pandemic to maintain safety and determine which adaptations will remain after the pandemic. METHODS: An original 34-question survey was sent by mail to a randomized selection of practicing orthodontic specialists (n = 1000). Questions included the changes made during the pandemic in 4 categories (infection control, social distancing, appliance type, and teleorthodontics) and whether those changes will remain postpandemic. RESULTS: The use of personal protective equipment increased during the pandemic, with a significant decrease anticipated after the pandemic. The most common aerosol modification during the pandemic and predicted after the pandemic was using an assistant with high-volume suction (61% and 49%, respectively; P = 0.0013). Ninety-six percent of orthodontists changed their waiting room protocol during the pandemic, but only 23% plan to continue that practice (P <0.0001). Forty-two percent of orthodontists increased clear aligners during the pandemic in response to patient demand (91%). The use of teleorthodontics increased from 8% to 68% during the pandemic and is expected to decrease significantly postpandemic. Virtual appointments are anticipated to be used for screening and consultations of new patients and monitoring active patients in clear aligners but not fixed appliances. CONCLUSIONS: The specialty recommended patient safety modifications during the coronavirus disease 2019 pandemic. Postpandemic, enhanced personal protective equipment is expected to decrease, and high-volume suction will likely be continued for aerosol-producing procedures. Teleorthodontics will likely remain in limited use.

Patient perspectives on teledentistry and face-to-face doctor interaction during orthodontic treatment.

INTRODUCTION: Teledentistry in orthodontics is growing, yet patient preferences for its use is unknown. This study aimed to determine the perceived value of doctor-to-patient face-to-face interaction, convenience, and attitudes toward specific uses of teledentistry among orthodontic patients. METHODS: Private practice orthodontists emailed an electronic survey to active patients. Patients aged ≥18 years completed the survey regarding their treatment. Parents of patients aged <18 years completed a separate survey regarding their child's treatment. Responses were compared on the basis of patient characteristics (adult vs child, braces vs clear aligners, etc). RESULTS: Three hundred and seventy-seven respondents from 8 orthodontic practices participated in the survey. Eighty-five percent of parents considered face-to-face interaction important, and 85% said that their child's treatment fit conveniently into their schedule. Adult responses were 86% and 89%, respectively. Adult preference for face-to-face was significantly higher than parents of adolescent patients (83% vs 78%; P = 0.038). Adults treated with clear aligners were less likely to strongly agree that their treatment fitted conveniently in their schedule (51% vs 76% in braces; P = 0.0490) and were more likely to be interested in using teledentistry (27% vs 18% in braces; P = 0.0429). CONCLUSIONS: Most orthodontic patients prefer to be seen face-to-face. This is due to the high value placed on face-to-face interaction with the orthodontist. Most patients do not consider their treatment inconvenient. Patients prefer that teledentistry be used to enhance communication as opposed to replacing face-to-face interaction. Implementing teledentistry in orthodontics should be applied on a patient-to-patient basis with continued emphasis on the doctor-patient relationship.

Perceived efficacy of extrusion of maxillary lateral incisors with aligners.

INTRODUCTION: This study aimed to assess the perceived efficacy of aligners (Invisalign; Align Technology, Santa Clara, Calif) at performing extrusive movements of maxillary lateral incisors and to evaluate and compare differences in treatment planning protocols and other interventions used when required between orthodontists and general dentists with various degrees of experience. METHODS: An original 18-question survey was sent by mail to a randomized and geographically proportionate selection of orthodontic specialists (N = 400) and general dentists (N = 400) listed as providers on the Invisalign Web site. The data were analyzed using analysis of variance and chi-square tests. RESULTS: One hundred twenty-six providers responded to the survey (15.8% response rate), including 36 general dentists and 90 orthodontists. Overall, the average perceived efficacy was 4.71 out of 10 (95% confidence interval, 4.28-5.14). The threshold for identification of tracking issues was significantly associated with provider type (P = 0.0305). General dentists were significantly more likely to prefer an optimized attachment (P = 0.0001), whereas orthodontists were significantly more likely to prefer a gingivally-beveled horizontal rectangular attachment (P <0.0001). A refinement scan was the most common intervention method, followed by the bootstrap technique. CONCLUSIONS: The average perceived efficacy for extruding maxillary lateral incisors with aligners was 4.71 out of 10. Orthodontists had a lower tolerance than general dentists for tracking issues. A refinement scan was the most common method of intervention. General dentists and orthodontists differed in their treatment planning preferences and timing of intervention.

Overbite recognition and factors affecting esthetic tolerance among laypeople.

OBJECTIVES: To determine recognition ability and the levels of esthetic tolerance of deep bite and anterior open bite (AOB) among laypeople and investigate the factors affecting levels of tolerance. MATERIALS AND METHODS: Using a questionnaire, laypeople (N = 100) were examined, and overbite was measured. They were tested for whether they recognized deep bite and AOB. Esthetic tolerance thresholds for deep bite and AOB were selected by incremental depiction in grayscale images. Stepwise logistic regression analyses were used to quantify the effect of recognition and other factors (age, sex, education level, occupation, history of orthodontic treatment, interest in orthodontic treatment or retreatment, and overbite presence) affecting the tolerance of overbite problems (α = 0.05). RESULTS: Of the participants, 55% and 94% recognized deep bite and AOB, respectively. Participants with a deep bite were significantly more likely to esthetically tolerate deep bite compared with those without a deep bite (odds ratio [OR], 3.57; 95% confidence interval [CI], 1.29-9.89). Participants who recognized a deep bite problem had significantly lower esthetic tolerance to deep bite compared with participants who did not recognize a deep bite (OR, 0.17; 95% CI, 0.06-0.45). None of the other eight chosen factors significantly affected the tolerance level of AOB (P > .05). CONCLUSIONS: Participants with a deep bite or those who did not recognize a deep bite had significantly higher esthetic tolerance of deep bite than those without or those who recognized the problem (P < .05).

Predicting Interest in Orthodontic Aligners: A Google Trends Data Analysis.

Aligners are an example of how advances in dentistry can develop from innovative combinations of 3D technologies in imaging, planning and printing to provide new treatment modalities. With increasing demand for esthetic orthodontic treatment, aligners have grown in popularity because they are esthetically more pleasing and less obstructive to oral hygiene and other oral functions compared to fixed orthodontic appliances. To observe and estimate aligner treatment interest among Google Search users, Google Trends data were obtained and analyzed for the search term, "Invisalign". A prediction of interest for the year 2022 for three European Union countries with the highest GDP was developed. "Invisalign" was chosen to represent all orthodontic aligners as the most searched term in Google Trends for aligners. This is the first study to predict interest in the query "Invisalign" in a Google search engine. The Prophet algorithm, which depends on advanced statistical analysis methods, positions itself as an automatic prediction procedure and was used to predict Google Trends data. Seasonality modeling was based on the standard Fourier series to provide a flexible model of periodic effects. The results predict an increase in "Invisalign" in Google Trends queries in the coming year, increasing by around 6%, 9% and 13% by the end of 2022 compared to 2021 for France, Italy and Germany, respectively. Forecasting allows practitioners to plan for growing demand for particular treatments, consider taking continuing education, specifically, aligner certification courses, or introduce modern scanning technology into offices. The oral health community can use similar prediction tools and methods to remain alert to future changes in patient demand to improve the responses of professional organizations as a whole, work more effectively with governments if needed, and provide better coordination of care for patients.

A comparison of patient testimonials on YouTube of the most common orthodontic treatment modalities: Braces, in-office aligners, and direct-to-consumer aligners.

INTRODUCTION: The aims of this study were to (1) investigate and compare the educational value of the most popular YouTube (www.youtube.com; Google, San Bruno, Calif) orthodontic patient testimonials between braces, in-office aligners (IOA), and direct-to-consumer aligners (DTCA), and (2) classify the emotional response of the viewers through sentiment analysis of the video comments. METHODS: Three different phrases relevant to braces, IOA, and DTCA were searched on YouTube. The 20 most popular patient testimonial videos meeting the criteria for each group were selected for a total of 60 videos. Using the YouTube application program interface for each video, 13 video metrics were extracted. An information completeness score was assigned, and the video comments were analyzed using sentiment analysis software. RESULTS: The 60 videos included were viewed 34.4 million times by internet users. Braces videos had significantly more likes, comments, and a higher viewer interaction score than the IOA and DTCA videos. IOA videos had a higher median information completeness score than braces and DTCA videos. Of the 5149 video comments with polarity, 53.6% were positive, and 46.4% were negative (P <0.0001). There was no significant association between the treatment modality and positive or negative comments (P = 0.5679). CONCLUSIONS: There is high user engagement on YouTube with orthodontic patient testimonials. YouTube users interact with braces patient testimonials the most. YouTube viewers' comments on orthodontic patient testimonials express more positive sentiment than negative sentiment. There was no significant difference in positive and negative sentiment between the video comments for the 3 different treatment modalities.

Separation of aligning and leveling stages to control mandibular incisor inclination: A randomized clinical trial.

OBJECTIVE: To determine whether separating the alignment and leveling phases can reduce proclination of the mandibular incisors. METHODS: Eligibility criteria included Class I subjects with an irregularity index of 3-5 mm, 3-4 mm curve-of-Spee (COS), and non-extraction treatment. Thirty adults were randomly allocated into two groups: (1) Control group was leveled and aligned simultaneously with flat archwires progressively to 0.016x0.022-in stainless-steel; (2) Experimental group was aligned first with 0.014-in-superelastic NiTi with mild accentuated COS, then leveled using 0.016x0.022-in beta-titanium accentuated COS archwires and gradually reduced the curve until flat. Mandibular incisor position and inclination were evaluated by cephalometric analysis. COS and irregularity index were evaluated in study models. Assessment was conducted twice after 0.016-in NiTi and after 0.016x0.022-in stainless-steel archwire placements. Dental changes from cephalograms and models were compared within group using paired t-test and between groups using independent t-test. RESULTS: Control group: Round-wire-phase, mandibular incisors tipped labially (4.38° and 1 mm) with intrusion (-1.13 mm); Rectangular-wire-phase, mandibular incisors further intruded and proclined (-0.63 mm and 1.38°). Experimental group: During aligning with round accentuated COS archwires, mandibular incisors tipped very slightly labially (0.75° and 0.50 mm) with no significant intrusion; during leveling with rectangular archwires, incisors majorly intruded (1.75 mm) with slight proclination (1.81°). The experimental group had significant less incisor proclination (control: 5.76°, experimental: 2.56°) with more incisor intrusion (control: -1.75 mm, experimental: -2.13 mm). The COS in experimental group showed significant greater reduction (-2.88 mm) than that of the control group (-1.69 mm). CONCLUSION: In control group, mandibular incisor proclination was markedly observed in round archwires, with further proclination caused by rectangular archwires. In experimental group, minimal proclination was exhibited when accentuated COS round archwires were used for aligning. Leveling with rectangular archwires caused less proclination with more COS reduction.

Separation of aligning and leveling stages to control mandibular incisor inclination: A randomized clinical trial

ABSTRACT Objective: To determine whether separating the alignment and leveling phases can reduce proclination of the mandibular incisors. Methods: Eligibility criteria included Class I subjects with an irregularity index of 3-5 mm, 3-4 mm curve-of-Spee (COS), and non-extraction treatment. Thirty adults were randomly allocated into two groups: (1) Control group was leveled and aligned simultaneously with flat archwires progressively to 0.016x0.022-in stainless-steel; (2) Experimental group was aligned first with 0.014-in-superelastic NiTi with mild accentuated COS, then leveled using 0.016x0.022-in beta-titanium accentuated COS archwires and gradually reduced the curve until flat. Mandibular incisor position and inclination were evaluated by cephalometric analysis. COS and irregularity index were evaluated in study models. Assessment was conducted twice after 0.016-in NiTi and after 0.016x0.022-in stainless-steel archwire placements. Dental changes from cephalograms and models were compared within group using paired t-test and between groups using independent t-test. Results: Control group: Round-wire-phase, mandibular incisors tipped labially (4.38° and 1 mm) with intrusion (-1.13 mm); Rectangular-wire-phase, mandibular incisors further intruded and proclined (-0.63 mm and 1.38°). Experimental group: During aligning with round accentuated COS archwires, mandibular incisors tipped very slightly labially (0.75° and 0.50 mm) with no significant intrusion; during leveling with rectangular archwires, incisors majorly intruded (1.75 mm) with slight proclination (1.81°). The experimental group had significant less incisor proclination (control: 5.76°, experimental: 2.56°) with more incisor intrusion (control: -1.75 mm, experimental: -2.13 mm). The COS in experimental group showed significant greater reduction (-2.88 mm) than that of the control group (-1.69 mm). Conclusion: In control group, mandibular incisor proclination was markedly observed in round archwires, with further proclination caused by rectangular archwires. In experimental group, minimal proclination was exhibited when accentuated COS round archwires were used for aligning. Leveling with rectangular archwires caused less proclination with more COS reduction.

RESUMO Objetivo: Avaliar se separar os estágios de alinhamento e nivelamento reduz a projeção dos incisivos inferiores. Métodos: Os critérios de inclusão foram indivíduos Classe I com índice de irregularidade de 3-5mm, Curva de Spee (CS) de 3-4mm e tratamento sem extrações. Trinta adultos foram alocados aleatoriamente em dois grupos: o Grupo Controle (1) foi simultaneamente alinhado e nivelado com arcos planos progressivamente até atingir o 0,016" x 0,022" de aço inoxidável; o Grupo Experimental (2) foi inicialmente alinhado com arcos superelásticos NiTi 0,014" com CS levemente aumentada, em seguida nivelado com arcos de beta-titânio 0,016" x 0,022" com CS acentuada, que foi gradualmente reduzida até ficar plana. A posição e inclinação dos incisivos inferiores foram avaliadas por meio de análise cefalométrica. A CS e o índice de irregularidade foram avaliados por meio de modelos de estudo. A avaliação foi realizada duas vezes, sendo após a inserção dos arcos NiTi 0,016" e dos arcos 0,016" x 0,022" de aço. As mudanças dentárias visualizadas nos cefalogramas e nos modelos foram comparadas dentro dos grupos utilizando teste t pareado e entre os grupos utilizando o teste t independente. Resultados: Grupo Controle: estágio de arco redondo: os incisivos inferiores se inclinaram vestibularmente (4.38° e 1 mm) e intruíram (-1,13mm); estágio de arco retangular: os incisivos inferiores intruíram e se projetaram adicionalmente (-0.63mm e 1,38°). Grupo Experimental: Durante o alinhamento com arcos redondos e CS acentuada, os incisivos inferiores se inclinaram levemente para vestibular (0,75° e 0,50mm), sem intrusão significativa; durante o nivelamento com arcos retangulares, os incisivos, em sua maioria, intruíram (1,75mm), com uma leve projeção (1,81°). O grupo experimental apresentou projeção dos incisivos significativamente menor (controle: 5,76°; experimental: 2,56°), com maior intrusão dos incisivos (controle: -1,75mm; experimental: -2,13mm). A CS no Grupo Experimental apresentou redução significativamente maior (-2,88 mm) do que no grupo controle (-1,69 mm). Conclusão: No Grupo Controle, foi observada de forma notória a projeção dos incisivos inferiores nos arcos redondos, com projeção adicional causada pelos arcos retangulares. No Grupo Experimental, foi observada uma projeção mínima quando foram utilizados arcos redondos com CS acentuada para alinhamento. O nivelamento com arcos retangulares causou menos projeção com maior redução da CS.

Orthodontists' and parents' perception of finished occlusion and willingness to extend treatment time.

INTRODUCTION: Patients and parents want shorter treatment times, but it is unclear whether they would compromise outcome quality to shorten treatment. The purpose of this study was to compare orthodontists' and parents' perceptions of finished occlusion and their willingness to extend treatment time to achieve improved outcomes. The effects of elapsed treatment time and patient compliance were also investigated. METHODS: Parallel surveys for orthodontists (n = 1000) and parents (n = 750) displayed simulated treatment outcomes of well-aligned teeth with occlusions in 1 mm increments from 3 mm Class III to 3 mm Class II. Participants rated their preferences on a visual analogue scale (VAS; 0-100) and specified whether they would extend treatment, and for how long, to improve the occlusion. RESULTS: Two hundred thirty-three orthodontists (23%) and 243 parents (32%) responded. Despite differences between the scores given (P < 0.0001), both groups rated Class I occlusion most acceptable (mean VAS = 93.9 and 80.7, respectively) and 3 mm Class III malocclusion least acceptable (mean VAS = 25.9 and 40.9, respectively). Parents were willing to extend treatment more often and for a greater time than orthodontists to improve results (P < 0.0001). In addition, parents were less willing to terminate treatment early (P < 0.05). Both groups perceived existing outcomes as more acceptable if the patient was noncompliant (P < 0.05), but elapsed time in treatment had no significant effect on ratings. CONCLUSIONS: For outcomes with well-aligned teeth, orthodontists and parents agreed on what the most and least acceptable occlusal relationships were. To achieve better outcomes, parents were willing to extend treatment duration more often and for a greater time than were orthodontists. In addition, parents were less willing than orthodontists to terminate treatment early.

A prospective clinical trial of the effects produced by the extrusion arch in the treatment of anterior open bite.

AIM: To evaluate the maxillary dentition effects of the extrusion arch for anterior open bite (AOB) correction in mixed dentition patients. MATERIALS AND METHODS: Fourteen subjects with an initial mean age of 9.17 ± 1.03 years presenting with dentoalveolar AOB (mean - 1.28 ± 1.46 mm) and normal facial pattern (FMA = 25.76°) were treated with an extrusion arch. The mean treatment period was 7.79 ± 2.58 months. Lateral cephalograms and dental models were taken before (T0) and after the correction of AOB (T1). Data were analyzed using paired t test to evaluate differences between T0 and T1. For all tests, a significance level of P < .05 was used. RESULTS: All patients achieved positive overbite at T1, with a mean increase of 3.07 mm. The maxillary incisors extruded 1.94 mm. Retroclination of the maxillary incisors (- 6.15°) and an increase in the interincisal angle (5.57°) were observed. There was a significant decrease in the distance between the incisal edge of the maxillary incisors and the molars (- 2.21 mm). There was significant mesial tipping of the maxillary molar (- 11.49°). Significant reductions of overjet (- 1.65 mm), arch perimeter (- 3.02 mm), and arch length (- 2.23 mm) were noted. The transverse maxillary intermolar distance did not change significantly. CONCLUSIONS: The use of a maxillary extrusion arch was effective in the treatment of AOB. Overbite increased due to incisor extrusion, as well as retroinclination and overjet reduction. However, side effects, such as mesial molar tipping and decreases in arch perimeter and length might occur.

The effect of orthognathic surgery on facial recognition algorithm analysis.

INTRODUCTION: The purpose of this study was to evaluate the ability of a publicly available facial recognition application program interface to calculate similarity scores for presurgical and postsurgical photographs of patients who underwent orthognathic surgeries. Our primary objective was to identify which surgical procedure(s) had the greatest effect(s) on the similarity score. METHODS: Existing photographs for 25 orthodontic-orthognathic patients were analyzed using the application program interface to calculate similarity scores between the presurgical and postsurgical photographs. Photographs from 2 presurgical timepoints were compared as controls. Both relaxed and smiling photographs were included to assess the added impact of a facial pose. Patient characteristics and surgery types were recorded for statistical analysis. Nonparametric Kruskal-Wallis rank-sum tests were performed to analyze the relationship between patient characteristics and similarity scores. Multiple comparisons Wilcoxon rank-sum tests were performed on the statistically significant characteristics. RESULTS: Recognition scores were significantly lower after orthognathic surgery at rest (P = 0.009) and smiling (P <0.001). Patients receiving both LeFort I and bilateral sagittal split osteotomy (BSSO) surgeries had a lower median similarity score compared with those that received only BSSO (P = 0.009) when comparing relaxed photographs before and after surgery. Similarly, for the score comparing presurgical relaxed photographs to postsurgical smiling photographs, patients that received both surgeries were found to have lower similarity scores compared with those receiving only BSSO (P = 0.036). CONCLUSIONS: Two-jaw surgeries were associated with a statistically significant decrease in similarity score when compared with 1-jaw procedure. Pose was also found to be a factor influencing similarity scores, especially when comparing presurgical relaxed photographs to postsurgical smiling photographs.