Which orthodontic articles are accessed online the most? Exploring article usage metrics along with citations and altmetrics.

OBJECTIVES: To investigate the current state of article usage metrics in orthodontics. MATERIALS AND METHODS: Out of all orthodontic journals listed in Journal Citation Reports 2022, the European Journal of Orthodontics and The Angle Orthodontist fulfilled the inclusion criteria. All journal issues published in 2021 were scrutinized for original research articles and systematic reviews/meta-analyses, and the following features were collected: article type, subject, title, number of words and authors, Altmetric Attention Score (AAS), X (formerly Twitter) posts, and Mendeley reads. Article citations, number of publications, and h-index of the last authors were retrieved from Web of Science (WoS). RESULTS: 181 articles were considered eligible. The median number of views and downloads of included articles was 1296 (range: 355-10,233) and 793 (range: 167-3629). Page views, downloads, and total views were significantly correlated with WoS citations (rho > 0.345; P < .001). There was no correlation between usage metrics, AAS, X posts, and Mendeley reads. Number of downloads were significantly higher in studies dealing with new technologies, and where the last author had 1-40 publications or an h-index of 0-30. CONCLUSIONS: Page views, downloads, and total views were positively correlated with WoS citations and, therefore, may serve as an early estimate of future citations. Significant variations in article downloads may be expected in relation to article subject, scientific productivity, and impact of the last authors.

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.

"Dear Doctor, greetings of the day!": A 1-year observational study of presumed predatory journal invitations.

BACKGROUND: This study aimed at investigating the predatory publishing phenomenon in orthodontics by analyzing the content of unsolicited e-mail invitations received within 12 months. METHODS: All electronic invitations for manuscript submission, review and editorial membership received between 1 October 2021 and 30 September 2022 were collected from an orthodontist's inbox. The following data were recorded for each e-mail: date, journal title and origin, requested contribution, e-mail language, relevance to the researcher's discipline, journal characteristics (claimed metrics, editorial services, article types accepted, and publication fees), journal/publisher contact information and online presence. Journal/Publisher legitimacy and publishing standards were evaluated by listing in the Beall's list of potential predatory journals and publishers, the Predatory Reports of Cabell's Scholarly Analytics, and the Directory of Open Access Journals. RESULTS: A total of 875 e-mail invitations deriving from 256 journals were retrieved within the observation period, with most of them soliciting article submissions. More than 76% of the solicitations originated from journals and publishers included in the blocklists used in the study. Salient features of predatory journals like flattering language, abundant grammatical errors, unclear publication charges and wide variety of article types and topics accepted for publication were confirmed for the examined journals/publishers. CONCLUSIONS: Nearly 8 out of 10 unsolicited e-mail invitations sent to orthodontists for scholarly contribution may be related to journals suspicious for publishing malpractices and suboptimal standards. Excessive flattering language, grammatical errors, broad range of submissions, and incomplete journal contact information were commonly encountered findings. Researchers in orthodontics should be alert to the unethical policies of illegitimate journals and their harmful consequences on the scientific literature.

Impact of COVID-19 Dentistry-Related Literature: An Altmetric Study.

INTRODUCTION: Scientific literature on COVID-19 has grown rapidly during the pandemic. The aim of this study was to provide a comprehensive overview of the popularity on the web of the available dental publications on COVID-19 and to examine associations amongst article characteristics, online mentions, and citations. MATERIALS AND METHODS: An Altmetric Explorer search was conducted for COVID-19 articles published in dental journals using 3 keywords: COVID-19, SARS-CoV-2, and pandemic. The following Altmetric data were collected: Altmetric attention score (AAS), mentions by news outlets, tweets, Mendeley readers, and Web of Science citations. Additionally, article title, type, topic, origin and open access status, journal title, quartile of impact factor (IF) distribution, and time lapse between COVID-19 pandemic onset and publication date were analysed. RESULTS: In all, 253 articles published in 48 dental journals were eligible for the study. AAS was significantly influenced by article topic, type, origin, and journal IF quartile. There was a negligible correlation between AAS and Web of Science citations. Mendeley was the only Altmetric source highly correlated with citations. CONCLUSIONS: There was substantial online interest in COVID-19 dentistry-related literature, as depicted by the AAS of the reviewed articles and social media metrics. Mendeley reader counts were highly correlated with citations, and they may therefore be valuable in research impact evaluation.

Public interest in Invisalign in developed and developing countries: A Google Trends analysis.

OBJECTIVE: To investigate long-term changes and possible seasonal variations in Google search volumes related to Invisalign in developed and developing countries. DESIGN: Cross-sectional, Google search-based study. METHODS: Google Trends (GT) was accessed to retrieve the Relative Search Volume (RSV) of Google queries related to the search term 'Invisalign' in 10 countries selected on the basis of population size, Internet usage and socioeconomic criteria between 1 January 2004 and 30 June 2021. The countries examined were the following: Australia, Brazil, Italy, Mexico, Philippines, Saudi Arabia, Spain, Thailand, UK and USA. By applying the time series decomposition method, the trend component and the seasonal variation were identified. RESULTS: Overall, RSVs regarding Invisalign have increased significantly in all countries with the developed countries outperforming developing countries throughout most of the observation period. There was no meaningful pattern when the trends were compared either on a monthly or quarterly basis. Similar peaks and valleys were found in Australia - Brazil, UK - USA, Italy - Spain and Saudi Arabia - Philippines - Thailand. CONCLUSIONS: Public interest in online information for Invisalign has grown significantly over the years across countries of diverse socioeconomic and cultural backgrounds while seasonal patterns were observed in the related Google searches. Seasonal fluctuations seemed to follow the academic calendar. The study results may have direct implications on practice management and professional development.

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

ABSTRACT 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.

RESUMO Objetivo: Comparar diferentes sistemas de tratamento com alinhadores transparentes (CAT), quanto à atratividade, aceitabilidade, visibilidade e disposição a pagar, por parte de alunos (primeiro e último anos) e instrutores de Odontologia. Métodos: Um questionário elaborado para coletar informações sobre preferências e intenções estéticas, em relação a sete sistemas CAT, foi distribuído para 120 alunos de graduação e instrutores do Academic Centre for Dentistry Amsterdam (ACTA). Modelos de riscos proporcionais e modelos de equação de estimação generalizada para a média da população foram usados para examinar a possível associação entre as características dos participantes, percepções estéticas e os sistemas CAT. Resultados: No geral, os sistemas CAT examinados receberam avaliações estéticas favoráveis. O nível de experiência foi significativamente associado com a disposição em pagar mais por sistemas CAT do que por aparelhos ortodônticos fixos. Não houve associação entre sexo, histórico de tratamento ortodôntico anterior, satisfação com a própria aparência dentária, potencial interesse em tratamento, visibilidade do alinhador e disposição em pagar mais. Os sistemas CAT foram significativamente associados à visibilidade percebida, aceitabilidade e atratividade dos alinhadores por alunos e instrutores. Conclusões: Os sistemas CAT foram considerados, em grande parte, atraentes e aceitáveis para tratamentos futuros pelos instrutores e alunos do curso de Odontologia. A disposição em pagar mais pelos sistemas CAT foi significativamente associada ao nível de especialização, com os instrutores parecendo mais relutantes em pagar mais pelo CAT.

Comment on Sycinska-Dziarnowska et al. The Implications of the COVID-19 Pandemic on the Interest in Orthodontic Treatment and Perspectives for the Future. Real-Time Surveillance Using Google Trends. Int. J. Environ. Res. Public Health 2021, 18, 5647.

With great interest we have read the recently published study titled "The Implications of the COVID-19 Pandemic on the Interest in Orthodontic Treatment and Perspectives for the Future. Real-Time Surveillance Using Google Trends" [...].

Author self-citation in orthodontics is associated with author origin and gender.

BACKGROUND: The aims of this bibliometric study were to determine author self-citation trends in high-impact orthodontic literature and to investigate possible association between self-citation and publication characteristics. METHODS: Six orthodontic journals with the highest impact factor as ranked by 2017 Journal Citation Reports were screened for a full publication year (2018) for original research articles, reviews, and case reports. Eligible articles were scrutinized for article and author characteristics and citation metrics. Univariable and multivariable negative binomial regression was used to examine associations between self-citation incidence and publication characteristics. RESULTS: Medians for author self-citation rate of the most self-citing authors and self-citations were 3.03% (range 0-50) and 1 (range 0-19), respectively. In the univariable analysis, there was no association between self-citation counts and study type (P = 0.41), article topic (P = 0.61), number of authors (P = 0.62), and rank of authors (P = 0.56). Author origin (P = 0.001), gender (P = 0.001) and journal (P = 0.05) were associated with self-citation counts and in the multivariable analysis only origin and gender remained strong self-citation predictors. Asian authors and females self-cited significantly less often than all other regions and male authors. CONCLUSIONS: Authors in orthodontics do not self-cite at a frequency that suggests potential citation manipulation. Author origin and gender were the only variables associated with citations counts. More bibliometric research is necessary to draw solid conclusions about author self-citation trends in orthodontic literature.

Class II Division 1 malocclusion treatment with extraction of maxillary first molars: Evaluation of treatment and post-treatment changes by the PAR Index.

OBJECTIVE: To investigate occlusal result and post-treatment changes after orthodontic extraction of maxillary first permanent molars in patients with a Class II division 1 malocclusion. SETTING AND SAMPLE: Retrospective longitudinal study in a private practice, with outcome evaluation by an independent academic hospital. Ninety-six patients (53 males, 43 females) consecutively treated by one orthodontist with maxillary first permanent molar extraction were studied, divided into three facial types, based on pre-treatment cephalometric values: hypodivergent (n = 18), normodivergent (n = 21) and hyperdivergent (n = 57). METHODS: Occlusal outcome was scored on dental casts at T1 (pre-treatment), T2 (post-treatment) and T3 (mean follow-up 2.5 ± 0.9 years) using the weighted Peer Assessment Rating (PAR) Index. The paired sample t test and one-way ANOVA followed by Tukey's post hoc test were used for statistical analysis. RESULTS: PAR was reduced by 95.7% and 89.9% at T2 and T3, respectively, compared with the start of treatment. The largest post-treatment changes were found for overjet and buccal occlusion. Linear regression analysis did not reveal a clear effect (R-Square 0.074) of age, sex, PAR score at T1, incremental PAR score T2-T1, overjet and overbite at T1, and facial type on the changes after treatment (incremental PAR score T3-T2). CONCLUSIONS: The occlusal outcome achieved after Class II division 1 treatment with maxillary first permanent molar extractions was maintained to a large extent over a mean post-treatment follow-up of 2.5 years. Limited changes after treatment were found, for which no risk factors could be discerned.

Tracking trends of transgender health research online: are researchers and the public on the same page?

Altmetric Explorer was searched for the most popular online articles published in Pubmed-indexed journals. The 75 articles with the highest Altmetric Attention Score (AAS) were screened for article information (date, journal, access), authorship (number of authors, affiliation and origin of the corresponding author), and research (type, subject, funding). The reviewed articles displayed a mean AAS of 241.52, were broadcast 17.03 times by news agencies, posted on Twitter 101.47 times, downloaded by 67.21 Mendeley readers, and received 62.67 citations. There was intense online interest in the transgender health literature, mainly related to mental health and social well-being. Online visibility of transgender health articles was not significantly correlated with citation counts, implying that the public, likely including transgender persons and allies, may place emphasis on different health issues than scholars. Monitoring altmetrics and interactions on electronic media may help researchers conduct research that is more meaningful to transgender individuals, and to society in general.

Students' awareness of LGBT resources in Dutch dental schools.

OBJECTIVES: The aim of this survey-based study was to investigate dental students' perceptions regarding the available services and facilities for LGBT persons in Dutch dental school administrations. METHODS: A 19-item questionnaire, originally developed in English, was implemented for the study purposes. Translation into Dutch as well as cross-cultural and conceptual adaptation were performed according to well-established guidelines. A link to the survey was sent via e-mail to all registered undergraduate students at the Academic Center for Dentistry Amsterdam (ACTA), and the dental schools of the University of Groningen (RUG) and the Radboud University Medical Center Nijmegen (RUMC). RESULTS: Of the 1,789 students initially invited to participate, 294 completed the online survey. Response rates among dental schools ranged between 7.60% and 20.24%. As a whole, the students of the participating dental schools were not cognizant of existing resources for LGBT students. There were significant differences in students' perceptions across schools, with RUG students being significantly less aware of LGBT resources compared to ACTA and RUMC (P < 0.05). Students' perceptions were not significantly influenced by school, sexual preference, and year of study (P > 0.05). No significant differences were observed in the responses of LGBT and non-LGBT students (P > 0.05). CONCLUSIONS: Undergraduate students were generally not aware of LGBT resources in Dutch dental schools. This lack of knowledge calls for attention by dental school administrators, program directors, and faculty to foster a visible, comprehensive, culturally competent environment in dental education settings in The Netherlands.

The informative value and design of orthodontic practice websites in The Netherlands.

BACKGROUND: The aims of this cross-sectional study were to investigate the regulatory compliance of Dutch practice websites offering orthodontic services, readability of the available treatment information, website design as well as possible relationship with practice location and professional qualification of practitioners. METHODS: A comprehensive Internet search was performed using the Google search engine and five relevant terms in Dutch. Eligibility screening of the first 50 results of each search led to the final inclusion of 111 websites. The content of the selected websites was evaluated in terms of compliance to international regulations on ethical advertising guidelines (CED), treatment information text readability using Flesch Reading Ease Score (FRES), and website design using the BDC assessment tool. RESULTS: Reporting of websites according to CED guidelines covered on average 85% of the mandatory items. No significant differences were observed between dental and orthodontic practices, and between practices located in densely and sparsely populated regions (P > 0.05). The mean FRES of the displayed information indicated difficult-to-understand text. BDC scores of multi-location practices were significantly higher than the rest (P < 0.006). CONCLUSIONS: The websites of orthodontic practices in The Netherlands do not fully comply with CED guidelines on ethical advertising. Readability of the displayed information and website technical performance needs to be further optimized.

How has the dental literature evolved over time? Analyzing 20 years of journal self-citation rates and impact factors.

Objective: As journal impact factors (IFs) can be artificially inflated by excessive journal self-citation practices, research quality evaluation based solely on IF ranking may be manipulated and, therefore, ethically challenged. This study aimed to analyze the longitudinal development of journal self-citation rates (SCRs) and IFs in dental literature and to determine possible confounders.Methods: Twenty-eight journals with scope within general dentistry and (sub)specialties listed in 1997-2016 Journal of Citation Reports® were scrutinized. The following information was retrieved: publication year, total number of citations, number of self-citations, IF, corrected IF, and SCR.Results: Endodontic journals had the highest SCR (median = 35.3, IQR = 21.6-47.5), journals related to periodontics had the lowest (median = 14.7, IQR = 8.9-25.5). Periodontics had the highest IF (median = 2.1, IQR= 1.7-2.8) and general dentistry had the lowest (median = 0.9, IQR = 0.7-1.2). SCR significantly decreased over time (p < .0001) by 1 unit per year. Additionally, 1 unit increase in corrected IF resulted in 15.2 units decrease in SCR. IFs significantly increased 0.06 units per year (p < .000).Conclusions: Overall, favourable changes in citation metrics have been observed for dental journals during the 20-year observation period. SCR significantly decreased per observation year whereas IFs significantly increased, indicating a healthy publishing environment in the dental literature. SCR was regulated both by time and corrected IF.

Concurrent validity and reliability of cephalometric analysis using smartphone apps and computer software.

OBJECTIVES: To assess the diagnostic accuracy of two smartphone cephalometric analysis apps compared with Viewbox software. MATERIALS AND METHODS: Pretreatment digital lateral cephalograms of 50 consecutive orthodontic patients (20 males, 30 females; mean age, 19.1 years; SD, 11.7) were traced twice using two apps (ie, CephNinja and OneCeph), with Viewbox used as the gold standard computer software program. Seven angular and two linear measurements, originally derived from Steiner cephalometric analysis, were performed. RESULTS: Regarding validity, intraclass correlation coefficients (ICCs) ranged from .903-.983 and .786-.978 for OneCeph vs Viewbox and CephNinja vs Viewbox, respectively. The ICC values for intratool reliability ranged from .647-.993. None of the CephNinja measurements was below the recommended cutoff values of ICCs for reliability. CONCLUSIONS: OneCeph has a high validity compared with Viewbox, while CephNinja is the best alternative to Viewbox regarding reliability. Smartphone apps may have a great potential in supplementing traditional cephalometric analysis.

Journal Self-Citation Rates and Impact Factors in Dentistry, Oral Surgery, and Medicine: A 3-year Bibliometric Analysis.

OBJECTIVES: The objective of this study was to evaluate the evolution of journal self-citation rates (SCRs) and impact factors (IFs) over time in the dental journals. MATERIALS AND METHODS: The journals listed under the category "dentistry, oral surgery, and medicine" in the Journal Citation Reports for the years 2014-2016 were screened for the following: citations and self-citations to years used in IF calculation, IF, IF without self-citations (corrected IF), SCR, and quartile of the IF distribution the journal occupied (Q1-Q4). Additional data regarding the number of issues published annually, journal's access options, and country of publication were extracted from the "Journal Profile Page." RESULTS: The median SCR significantly declined between 2014 and 2016 (13.725 [0-57.049], 12.687 [0-52.326], and 10.667 [0-53.208], respectively [P < .05]), while at the same time, IFs and corrected IFs significantly increased. SCR was significantly higher in subspecialty journals than that in general journals, as well as in the ones publishing more issues per year. Open-access journals tended to present lower SCR compared to journals requiring payment. No statistically significant differences in SCR were observed with respect to the origin and quartile. Nonsignificant correlations (r < 0.3, P > .05) were found for SCR-IF and SCR-corrected IF for all years. CONCLUSIONS: There was a statistically significant decrease in SCR during the observation period. SCR was not correlated to IF of dental journals. Subspecialty journals and journals publishing more frequently presented significantly higher SCRs. These findings suggest favorable publishing conditions and citation practices in the dental literature.

Autotransplantation of teeth with incomplete root formation: a systematic review and meta-analysis.

OBJECTIVES: The objective of this systematic review and meta-analysis was to determine the rates of survival and success and the complications related to autotransplantation of teeth with incomplete root formation. Additionally, we attempted to identify the prognostic factors that influence the outcome of tooth autotransplantation. MATERIALS AND METHODS: A literature search for all data published until July 2016 was conducted. Inclusion and exclusion criteria were specified. Risk of bias was assessed with the Newcastle checklist. Meta-analysis was performed by using the DerSimonian-Laird random effect model. The 1-, 5-, and 10-year survival rates and the weighted estimated survival, success, and complication rates per year were calculated. RESULTS: Thirty-two studies were included for analysis. The survival rates reported after 1, 5, and 10 years were 97.4, 97.8, and 96.3%, respectively. The annual weighted estimated survival rate (98.2%), success rate (96.6%), and complication rates in terms of ankylosis (2.0%), root resorption (2.9%), and pulp necrosis (3.3%) were analyzed. No firm conclusions could be drawn with respect to the prognostic factors due to insufficient evidence of high quality. CONCLUSION: The survival and success rates of autotransplantation of teeth with incomplete root formation were high (> 95%), with a low rate of complications (< 5%). CLINICAL RELEVANCE: Current evidence from the literature on autotransplantation of teeth with incomplete root formation shows favorable survival and success rates and low complication rates, indicating it is a reliable treatment option.

"My Invisalign experience": content, metrics and comment sentiment analysis of the most popular patient testimonials on YouTube.

BACKGROUND: The aim of the study was to investigate the popularity, content of Invisalign patient testimonials on YouTube, as well as the sentiment of the related comments. METHODS: Using the term "Invisalign experience," the top 100 results on YouTube by view count were screened for English spoken patient videos that attracted comments. Video information (time since video upload, sponsorship), engagement metrics (comments, likes, dislikes, subscriptions), and views were collected. Videos were rated for information completeness (ICS), and comments were classified by origin and content. The emotional loading of the comments was measured using automated sentiment analysis. RESULTS: The 40 reviewed testimonials scored an average ICS of 3.78 (SD 0.97). ICS, time since upload, and video duration did not appear to significantly influence the number of views, subscriptions, likes, dislikes, and comments. There was a statistically significant difference (P = 0.03) between mean positive (2.01, SD 0.95) and negative sentiment scores (- 1.90, SD 1.14). Commenter's status and overall comment on video were significantly associated with positive sentiment scores. There was a significant association between sponsorship, commenter's status, overall comment on video, focus of concern, perceived Invisalign's disadvantages, and increased negative sentiment scores. CONCLUSIONS: Engagement of audience and views of the most popular Invisalign patient testimonials were not significantly influenced by completeness of information, video duration, and lifespan. The sentiment of viewers' comments about Invisalign treatment was significantly more positive and was significantly associated with their status, content, and sponsorship of videos. Orthodontic trends on YouTube need to be cautiously monitored for planning interventions that improve patients' knowledge about orthodontics.

Looking Beyond Traditional Metrics in Orthodontics: An Altmetric Study on the Most Discussed Articles on the Web.

Objective: To evaluate the online visibility of the most popular orthodontic articles in Web platforms in relation to publication details and citations. Materials and Methods: Altmetric Explorer (Altmetric LLP, London, UK) was searched for articles published in 11 orthodontic journals without time limits in publication and citation on social media. The 200 articles with the highest Altmetric Attention Score (AAS) were collected and screened for data related to publication (date, journal, access), authorship (number of authors, affiliation and origin of the corresponding author), and research (type, subject, funding). Citation counts were harvested from Scopus. Results: The top 200 articles presented a median AAS of 8.0 (range: 5.0-196.0), and were mostly bookmarked in Mendeley (median: 16.6 references; range: 0-199.0). American Journal of Orthodontics & Dentofacial Orthopedics, European Journal of Orthodontics and The Angle Orthodontist contributed 86 per cent of the total number of research outputs. Studies investigating socio-demographics had significantly higher AAS compared to diagnostic studies (median AAS: 19.0; range: 7.0-34.0; versus median AAS: 6.0; range: 5.0-10.0. No other study parameter was found to be statistically significant. AAS did not correlate to the number of citations as reported in Scopus. Limitations: The early stage of altmetrics and their complementary role in assessing together with the citation-based metrics the research impact need to be acknowledged in the interpretation of the results. Conclusions: Visibility of orthodontic articles on the Web is not significantly correlated with citations. Studies on socio-demographics had significantly higher number of online mentions. More constructive online presence of orthodontic journals is needed to reinforce dissemination of research data among scholars and non-scholars.

Twin Block appliance with acrylic capping does not have a significant inhibitory effect on lower incisor proclination.

OBJECTIVE: To investigate the effect of acrylic capping, treatment duration, overjet, and lower incisor inclination on the posttreatment tooth position in patients treated with 2 Twin Block (TB) appliance versions. MATERIALS AND METHODS: Cephalograms of 56 patients with Class II malocclusion (21 boys, 35 girls; mean age before treatment [T1] = 12.5 years; standard deviation, 0.7) treated with a TB appliance with either acrylic capping or ball-ended clasps on lower incisors were retrospectively collected and traced. Lower incisor inclination (L1-GoGn, L1-GoMe, L1-MP) was measured at T1 and after TB appliance removal (T2). Regression analysis was performed to evaluate the effect on the lower incisor inclination of appliance type, overjet, lower incisor inclination at T1, and treatment duration after adjusting for baseline measurements. RESULTS: Appliance design was not a significant predictor for either incisor inclination measurement (P< .05). Pretreatment lower incisor inclination was the only factor significantly associated with final tooth inclination (L1-GoGn: ß = 0.57, 95% confidence interval [CI] = 0.30, 0.84, P < .001; L1-GoMe: ß = 0.56, 95% CI = 0.28, 0.84, P < .001; L1-MP: ß = 0.46, 95% CI = 0.17, 0.75, P = .003). There was weak evidence that treatment duration excluding L1-MP (95% CI = -1.85, -0.02; P = .045) and overjet might be associated with inclination of lower incisors at T2. CONCLUSIONS: TB appliance design with acrylic capping on lower incisors appears not to significantly control incisor proclination. Pretreatment lower incisor inclination may be significantly associated with tooth inclination after active TB treatment and should be considered in treatment planning.