Search

The aim of this study was to identify and describe the characteristics of coronavirus (COVID-19)-disease related dental research in Brazil presented at the 38th Annual Meeting of the Brazilian Division of the International Association for Dental Research (SBPqO). A search was carried out in the proceedings of the meeting to retrieve all abstracts. Those containing the term "COVID-19" in titles, abstracts, or keywords, and/or those of which the scope approached a COVID-19-related topic were included. The variables extracted from abstracts were: presenter category, field of study, design, data collection method, population, affiliation, and authors' gender. Descriptive and inferential statistics were used, with a significance level of α = 0.05. The search retrieved 185 abstracts, 5 did not meet study eligibility criteria and were excluded. COVID-19-related research was presented by either aspiring/associate members (67.8%) or beginner members (32.2%). Data collection methods were predominantly digitally mediated (65%), followed by secondary data use (25%), and in-person data collection (7.2%). Irrespective of the role of authorship, there were a ratio of two female authors to each male. Among the last authors, the ratio was three females to each male. Female lead authors more frequently came from the Southeast region (71.8%; p = 0.470). There was an association between presenter category and study design (p = 0.012), clinical and epidemiological studies were more concentrated among experienced presenters. In conclusion, female dental researchers affiliated to southeastern institutions approached the topic of pandemic more frequently than male colleagues. The use of digital technology for data collection may have long-lasting impacts on the teaching and publication of dental research.

The FaceBase Consortium was established by the National Institute of Dental and Craniofacial Research in 2009 as a 'big data' resource for the craniofacial research community. Over the past decade, researchers have deposited hundreds of annotated and curated datasets on both normal and disordered craniofacial development in FaceBase, all freely available to the research community on the FaceBase Hub website. The Hub has developed numerous visualization and analysis tools designed to promote integration of multidisciplinary data while remaining dedicated to the FAIR principles of data management (findability, accessibility, interoperability and reusability) and providing a faceted search infrastructure for locating desired data efficiently. Summaries of the datasets generated by the FaceBase projects from 2014 to 2019 are provided here. FaceBase 3 now welcomes contributions of data on craniofacial and dental development in humans, model organisms and cell lines. Collectively, the FaceBase Consortium, along with other NIH-supported data resources, provide a continuously growing, dynamic and current resource for the scientific community while improving data reproducibility and fulfilling data sharing requirements., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2020. Published by The Company of Biologists Ltd.)

Background: Biomedical research has recently moved through three stages in digital healthcare: (1) data collection; (2) data sharing; and (3) data analytics. With the explosion of stored health data (HD), dental medicine is edging into its fourth stage of digitization using artificial intelligence (AI). This narrative literature review outlines the challenge of managing HD and anticipating the potential of AI in oral healthcare and dental research by summarizing the current literature., Summary: The basis of successful management of HD is the establishment of a generally accepted data standard that will guide its implementation within electronic health records (EHR) and health information technology ecosystems (HIT Eco). Thereby continuously adapted (self-) learning health systems (LHS) can be created. The HIT Eco of the future will combine (i) the front-end utilization of HD in clinical decision-making by providers using supportive diagnostic tools for patient-centered treatment planning, and (ii) back-end algorithms analyzing the standardized collected data to inform population-based policy decisions about resource allocations and research directions. Cryptographic methods in blockchain enable a safe, more efficient, and effective dental care within a global perspective. Key Message: The interoperability of HD with accessible digital health technologies is the key to deliver value-based dental care and exploit the tremendous potential of AI., (© 2019 S. Karger AG, Basel.)

Epidemiological investigations of early childhood oral health rely upon the collection of high-quality clinical measures of health and disease. However, ascertainment of valid and accurate clinical measures presents unique challenges among young, preschool-age children. The paper presents a clinical research protocol for the conduct of oral epidemiological examinations among children, implemented in ZOE 2.0, a large-scale population-based genetic epidemiologic study of early childhood caries (ECC). The protocol has been developed for the collection of information on tooth surface-level dental caries experience and tooth-level developmental defects of the enamel in the primary dentition. Dental caries experience is recorded using visual criteria modified from the International Caries Detection and Assessment System (ICDAS), and measurement of developmental defects is based upon the modified Clarkson and O'Mullane Developmental Defects of the Enamel Index. After a dental prophylaxis (toothbrushing among all children and flossing as needed), children's teeth are examined by trained and calibrated examiners in community locations, using portable dental equipment, compressed air, and uniform artificial light and magnification conditions. Data are entered directly onto a computer using a custom Microsoft Access-based data entry application. The ZOE 2.0 clinical protocol has been implemented successfully for the conduct of over 6000 research examinations to date, contributing phenotype data to downstream genomics and other "omics" studies of ECC and DDE, as well as traditional clinical and epidemiologic dental research.

Dental schools in the United States increasingly emphasize community-based practice targeting underserved populations. However, the impact on target populations remains largely undocumented. East Carolina University School of Dental Medicine (ECU SoDM) developed an integrated electronic health record database that aggregates patient data from all clinics in the ECU SoDM system and enables longitudinal assessment of the impact of clinical care on oral health outcomes. The aim of this study was to analyze the demographic and oral health characteristics data for eligible patients from June 2012 to March 2016. Data from 28,029 eligible patients were included. Except for expected variations in racial composition, the demographic data were similar across ECU SoDM clinics and indicated that the patient population represents a geographically diverse sample of outpatients. The mean decayed, missing, and filled teeth (DMFT) index was elevated in this population. Among the trends identified across subgroups were higher DMFT index in older patients and lower DMFT index for individuals of Hispanic or Latino ethnicity. Although the percentage of patients with dental caries overall rose steadily with age, the percentage with untreated dental caries generally fluctuated around 33%±5% without age-related trends. These data provide a baseline for evaluating changes over time and the impact of oral health care introduced to areas served by the ECU SoDM. These findings highlight the need for access to care and support the ECU SoDM's core mission.

Population-based linkage of patient-level information opens new strategies for dental research to identify unknown correlations of diseases, prognostic factors, novel treatment concepts and evaluate healthcare systems. As clinical trials have become more complex and inefficient, register-based controlled (clinical) trials (RC(C)T) are a promising approach in dental research. RC(C)Ts provide comprehensive information on hard-to-reach populations, allow observations with minimal loss to follow-up, but require large sample sizes with generating high level of external validity. Collecting data is only valuable if this is done systematically according to harmonized and inter-linkable standards involving a universally accepted general patient consent. Secure data anonymization is crucial, but potential re-identification of individuals poses several challenges. Population-based linkage of big data is a game changer for epidemiological surveys in Public Health and will play a predominant role in future dental research by influencing healthcare services, research, education, biotechnology, insurance, social policy and governmental affairs.

Introduction: There is limited literature on the impact of testing variables on the push-out bond test (POBT). This review identified designs of the POBT used in the endodontic literature and aimed to determine which experimental variables may influence the push-out bond strength (POBS)., Methods: A systematic review based on PRISMA guidelines was performed by searching the PubMed, SCOPUS, and Cochrane library databases using terms including push-out and dislocation resistance and descriptions of endodontic materials. Test variables assessed included method of root preparation, timing of sectioning compared with filling, thickness, diameter and taper of sections, and plunger size and velocity. The POBS of 3 common materials (gutta-percha and AH Plus, mineral trioxide aggregate, and Biodentine) were collected from investigations, and a comparison was attempted., Results: One hundred thirty-three studies assessed the POBS of root-filling materials, 68 assessed root repair cements/root-end filling materials, and 16 assessed orifice barrier materials other than mineral trioxide aggregate. There was significant variation in all of the assessed variables, resulting in a large range of reported values for the POBS of the various materials. Because of this heterogeneity in study design, no further statistical analysis of the impact of the test variables on POBS was possible., Conclusions: There was considerable variation in the POBT design used in endodontic research. Greater standardization is required for future research as well as accurate reporting for all test variables to assess the impact of specific design variables on POBS., (Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

The high prevalence of oral diseases and the persistent nature of socioeconomic inequalities in oral health outcomes across societies presents a significant challenge for public health globally. A debate exists in epidemiology on the merits of investigating population variations in health and its determinants over studying individual health and its individual risk factors. The choice of analytical unit for health outcomes at the population level has policy implications and consequences for the causal understanding of population-level variations in health/disease. There is a lack of discussion in oral epidemiology on the relevance of studying population variations in oral health. Evidence on the role of societal factors in shaping variations in oral health at both the individual level and the population level is also mounting. Multilevel studies are increasingly applied in social epidemiology to address hypotheses generated at different levels of social organization, but the opportunities offered by multilevel approaches are less applied for studying determinants of oral health at the societal level. Multilevel studies are complex as they aim to examine hypotheses generated at multiple levels of social organization and require attention to a range of theoretical and methodological aspects from the stage of design to analysis and interpretation. This discussion study aimed to highlight the value in studying population variations in oral health. It discusses the opportunities provided by multilevel approaches to study societal determinants of oral health. Finally, it reviews the key methodological aspects related to operationalizing multilevel studies of societal determinants of oral health., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Introduction: Reports on randomized clinical trials (RCTs) are of critical importance because readers of research often do not access the full text. This study aimed to assess the reporting quality of RCTs in 2 leading endodontic journals., Methods: Issues of 2 endodontic journals, the Journal of Endodontics and the International Journal of Endodontics, dated from 2012 to 2017 were hand searched to identify RCT reports. A 37-item checklist based on the Consolidated Standards of Reporting Trials statement was used to examine the completeness of RCT reporting., Results: One hundred nine RCT reports were included in this study. The majority were published in the Journal of Endodontics (82%). The mean overall reporting quality score was 65.0% (95% confidence interval, 77.3-66.5). Most (80%-100%) RCTs clearly reported the author/contact details, trial design, participant characteristics, number of participants, and recruitment status as well as the study's intervention(s), objective(s), outcome(s), and conclusions. Conversely, only 56 of the 109 articles (51%) satisfactorily reported all 5 items related to the randomization method. Registration of reviews was not reported in any of the included abstracts. Most of the studies included in this analysis did not report their RCT registration (22%), funding (35%), or protocols (23%)., Conclusions: The results of this study suggest that the reporting quality of RCTs in endodontic journals requires further improvement. Better reporting of RCTs is particularly important for ensuring the reliability of research findings and ultimately promoting the practice of evidence-based dentistry. Optimal RCT reporting should be encouraged, preferably by complying with the Consolidated Standards of Reporting Trials guidelines., (Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Introduction: The aim of this systematic review (SR) was to evaluate the quality of SRs and meta-analyses (MAs) in endodontics., Methods: A comprehensive literature search was conducted to identify relevant articles in the electronic databases from January 2000 to June 2017. Two reviewers independently assessed the articles for eligibility and data extraction. SRs and MAs on interventional studies with a minimum of 2 therapeutic strategies in endodontics were included in this SR. Methodologic and reporting quality were assessed using A Measurement Tool to Assess Systematic Reviews (AMSTAR) and Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA), respectively. The interobserver reliability was calculated using the Cohen kappa statistic. Statistical analysis with the level of significance at P < .05 was performed using Kruskal-Wallis tests and simple linear regression analysis., Results: A total of 30 articles were selected for the current SR. Using AMSTAR, the item related to the scientific quality of studies used in conclusion was adhered by less than 40% of studies. Using PRISMA, 3 items were reported by less than 40% of studies, which were on objectives, protocol registration, and funding. No association was evident comparing the number of authors and country with quality. Statistical significance was observed when quality was compared among journals, with studies published as Cochrane reviews superior to those published in other journals. AMSTAR and PRISMA scores were significantly related., Conclusions: SRs in endodontics showed variability in both methodologic and reporting quality., (Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Background: Despite the known benefits of a mixed methods approach in health research, little is known of its use in the field of population oral health., Objective: To map the extent of literature using a mixed methods approach to examine population oral health outcomes., Methods: For a comprehensive search of all the available literature published in the English language, databases including PubMed, Dentistry and Oral Sciences Source (DOSS), CINAHL, Web of Science and EMBASE (including Medline) were searched using a range of keywords from inception to October 2017. Only peer-reviewed, population-based studies of oral health outcomes conducted among non-institutionalised participants and using mixed methods were considered eligible for inclusion., Results: Only nine studies met the inclusion criteria and were included in the review. The most frequent oral health outcome investigated was caries experience. However, most studies lacked a theoretical rationale or framework for using mixed methods, or supporting the use of qualitative data. Concurrent triangulation with a convergent design was the most commonly used mixed methods typology for integrating quantitative and qualitative data. The tools used to collect quantitative and qualitative data were mostly limited to surveys and interviews., Conclusion: With growing complexity recognised in the determinants of oral disease, future studies addressing population oral health outcomes are likely to benefit from the use of mixed methods. Explicit consideration of theoretical framework and methodology will strengthen those investigations., (Copyright© 2018 Dennis Barber Ltd.)

Background: To prove that Caries Management by Risk Assessment (CAMBRA) can be successfully implemented in dental practices outside of the university setting, dentists in the San Francisco Bay Area (CA) were approached to participate in a Practice Based Research Network (PBRN) study. The overall goal of the CAMBRA-PBRN study was to recruit 30 dentists to perform a two-year study involving approximately 900 patients. Goal of the calibration study was to standardize and calibrate dentists potentially participating in the CAMBRA-PBRN study., Methods: To minimize inter-examiner variability in data collection, including classification of carious lesions and recording of existing restorations, participating dentists were trained and calibrated in accurate DMFS (decayed, missing, filled surfaces) charting. Dentists were also trained and calibrated to diagnose and differentiate between sound surfaces and non-cavitated caries lesions (International Caries Detection and Assessment - ICDAS scores 1 and 2) for posterior occlusal surfaces. Thirty dentists were calibrated to a single gold standard examiner (BJ) during 6 calibration sessions, between 2011 and 2014. Kappa statistics were used to determine inter-examiner reliability on 13 or more patients, aged 12-63 (average age 38 ± 15 years), per examiner during each session, resulting in 94 patient encounters over the course of all 6 sessions. To participate in the main study, examiners needed to achieve a minimum required kappa of 0.75. During the calibration process, examiners scored between 1036 and 2220 tooth surfaces., Results: The kappa values (unweighted kappa) of the participating dentists compared to the gold standard examiner ranged from 0.75 to 0.90, with an average kappa of 0.84 ± 0.03. 90% of the examiners achieved overall kappa values above 0.8. However, separate reliability for assessment of non-cavitated lesions, as in other studies, was lower (0.55 ± 0.15). Multiple subcategories were evaluated. All dentists reached sufficient reliability values to proceed into the study; nevertheless, one dentist discontinued with the study due to scheduling conflicts., Conclusions: The high inter-examiner reliability results have shown that dentists who work in primarily non-research based practices can be effectively standardized and calibrated in data collection, based on specific guidelines created to anticipate potential research study scenarios.

In situ caries research serves as a bridge between clinical research and laboratory studies. In this kind of research, volunteers wear a removable intraoral splint or prosthesis containing research samples. Many different in situ models exist to investigate secondary caries. This systematic review compared currently existing secondary caries models and their lesion progression per day values., Materials and Methods: Three databases (Medline, Embase, and Cochrane) were searched for relevant literature. Bias risk was assessed and model parameters and caries-related outcomes were extracted by 2 independent researchers. Where possible, caries-related outcomes were normalized by estimating lesion progression per day by dividing lesion depth extracted from microradiographic or microhardness data by the number of days the study lasted., Results: The literature search identified 335 articles. After eliminating duplicates and selection, 31 articles were included. The models differed greatly on factors such as sample location, presence of fluoride in the model, and analysis methods. Three main groups could be identified by sample placement; 68% of models placed samples palatally in the upper jaw, and the lower jaw model could be divided into the buccal (26%) and approximal (6%) areas. Average lesion progression in enamel next to composite was 4.3 ± 2.8 µm (range1.1-8.8 µm/day)., Discussion: Studies conducted with palatal models showed caries progression rates 2-5 times higher than the estimated clinical progression rates. Lesion progression per day could be a useful tool for future comparison of models and establishing a standardized model., (© 2018 S. Karger AG, Basel.)

Emerging evidence suggests that design flaws of randomized controlled trials can result in over- or underestimation of the treatment effect size (ES). The objective of this study was to examine associations between treatment ES estimates and adequacy of sequence generation, allocation concealment, and baseline comparability among a sample of oral health randomized controlled trials. For our analysis, we selected all meta-analyses that included a minimum of 5 oral health randomized controlled trials and used continuous outcomes. We extracted data, in duplicate, related to items of selection bias (sequence generation, allocation concealment, and baseline comparability) in the Cochrane Risk of Bias tool. Using a 2-level meta-meta-analytic approach with a random effects model to allow for intra- and inter-meta-analysis heterogeneity, we quantified the impact of selection bias on the magnitude of ES estimates. We identified 64 meta-analyses, including 540 randomized controlled trials analyzing 137,957 patients. Sequence generation was judged to be adequate (at low risk of bias) in 32% ( n = 173) of trials, and baseline comparability was judged to be adequate in 77.8% of trials. Allocation concealment was unclear in the majority of trials ( n = 458, 84.8%). We identified significantly larger treatment ES estimates in trials that had inadequate/unknown sequence generation (difference in ES = 0.13; 95% CI: 0.01 to 0.25) and inadequate/unknown allocation concealment (difference in ES = 0.15; 95% CI: 0.02 to 0.27). In contrast, baseline imbalance (difference in ES = 0.01, 95% CI: -0.09 to 0.12) was not associated with inflated or underestimated ES. In conclusion, treatment ES estimates were 0.13 and 0.15 larger in trials with inadequate/unknown sequence generation and inadequate/unknown allocation concealment, respectively. Therefore, authors of systematic reviews using oral health randomized controlled trials should perform sensitivity analyses based on the adequacy of sequence generation and allocation concealment.

The low prevalence of gingival recessions observed in orthodontic clinical practice may be assigned to the fact that in studies in which dehiscences and bone fenestrations are described as frequent, they were diagnosed based on: 1) dry skull studies; 2) areas with periosteal reflection together with flap; and 3) imaging techniques with low sensitivity to detect these defects, which have a delicate structure and function. In areas of pseudo-dehiscences and fenestrations, the periosteum and the alveolar cortical bone are very thin; also, they either have been removed during preparation of the dry specimens in the areas for analysis, or, alternatively, have not been investigated using an ideal imaging method.

Online tobacco cessation communities are beneficial but underused. Our study examined whether, among smokers participating in a web-assisted tobacco intervention (Decide2quit.org), specific characteristics were associated with navigating to BecomeAnEx.org, an online cessation community, and with subsequent quit rates. Among smokers (N = 759) registered with Decide2quit.org, we identified visitors to BecomeAnEx.org, examining associations between smoker characteristics and likelihood of visiting. We then tested for associations between visits and 6-month cessation (point prevalence). We also tested for an interaction between use of other online support-seeking (Decide2quit.org tobacco cessation coaches), visiting, and 6-month cessation. One quarter (26.0 %; n = 197) of the smokers visited BecomeAnEx.org; less than one tenth (7.5 %; n = 57) registered to participate in the online forum. Visitors were more likely to be female (73.0 vs. 62.6 % of non-visitors, P < 0.01) to have visited a cessation website before (33.0 vs. 17.4 %, P < 0.01) and to report quit attempts in the previous year (62.0 vs. 53.0 %, P = 0.03). In analyses of all participants, BecomeAnEx.org visiting was not associated with 6-month quit completion. Among participants who communicated with a coach, BecomeAnEx.org visiting also lacked a significant association with 6 month quit completion, although a non-significant trend toward quit completion in visitors was noted (OR 2.21, 95 % CI 0.81-3.1). Online cessation communities attract smokers with previous cessation website experience and recent quit attempts. Community visiting was not associated with quit rates in our study, but low use may have limited our power to detect differences. Further research should explore whether an additive effect can be achieved by offering community visitors support via online coaches., Competing Interests: During the study period, Dr. Cobb was employed by Legacy, a non-profit organization that owns and operates the BecomeAnEx.org website. Dr. Cutrona has received grant funding from Pfizer Independent Grants for Learning & Change. Adherence to ethical principles All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Introduction: Focus group methods have been increasingly used in dental research. However, although focus group methods appear quite simple and easy to carry out, there are a number of complexities that need to be considered., Method: The present integrative review was carried out to assess the usability of focus group methods for dental research., Results: Three key themes were identified from the qualitative review: the complexity of the method; benefits of focus group research for dentistry; and, the nature of the quality controls employed., Conclusion: A key strength of using focus groups is that they can enhance qualitative and quantitative methodologies by helping to clarify, extend, qualify, or challenge what has been found.

Aim: To develop a suitable protocol for screening extracted teeth so as to create anatomically well-balanced experimental groups for endodontic studies., Methodology: Sixty pairs (120 teeth) of contralateral premolars (CLPs) were collected. The evaluation of samples for anatomical features was performed in the following ways. First, the 120 teeth were divided into right and left sides (N = 60, each side), and the teeth of each side were screened individually according to regular inclusion criteria (parameters included mature apical foramen, canal type, canal curvature and tooth length). The similarity of the specimens was then evaluated. The second screening process evaluated the 60 pairs of CLPs using the same criteria. Finally, CBCT was used to establish a strict screening protocol to create well-balanced groups of CLPs., Results: In the first screening process, 80% (24/30) of the left and 61% (19/31) of the right side were selected out of teeth with mature foramina; but the included teeth had asymmetrical canal curvatures. In the second screening process, 28 pairs were selected after the exclusion of those with an immature foramen in one pair. Seventeen pairs in which the tooth length and canal curvature were symmetrical were selected from the 28 CLPs. In the third screening, only 21% (6/28) of CLPs passed the rigorous screening procedure and were identical for creating balanced experimental groups., Conclusions: Relatively, few pairs of contralateral teeth had anatomical symmetry. For endodontic studies, a strict and detailed scientific screening protocol is necessary to achieve well-balanced experimental groups., (© 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.)

Randomized controlled trials have long been considered the 'gold standard' for causal inference in clinical research. In the absence of randomized experiments, identification of reliable intervention points to improve oral health is often perceived as a challenge. But other fields of science, such as social science, have always been challenged by ethical constraints to conducting randomized controlled trials. Methods have been established to make causal inference using observational data, and these methods are becoming increasingly relevant in clinical medicine, health policy and public health research. This study provides an overview of state-of-the-art methods specifically designed for causal inference in observational data, including difference-in-differences (DiD) analyses, instrumental variables (IV), regression discontinuity designs (RDD) and fixed-effects panel data analysis. The described methods may be particularly useful in dental research, not least because of the increasing availability of routinely collected administrative data and electronic health records ('big data')., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Streptococcus mutans (S. mutans) is the major clinical pathogen responsible for dental caries. Its acid tolerance has been identified as a significant virulence factor for its survival and cariogenicity in acidic conditions. Small RNAs (sRNAs) are recognized as key regulators of virulence and stress adaptation. Here, we constructed three libraries of sRNAs with small size exposed to acidic conditions for the first time, followed by verification using qRT-PCR. The levels of two sRNAs and target genes predicted to be bioinformatically related to acid tolerance were further evaluated under different acid stress conditions (pH 7.5, 6.5, 5.5, and 4.5) at three time points (0.5, 1, and 2 h). Meanwhile, bacterial growth characteristics and vitality were assessed. We obtained 1879 sRNAs with read counts of at least 100. One hundred and ten sRNAs were perfectly mapped to reported msRNAs in S. mutans. Ten out of 18 sRNAs were validated by qRT-PCR. The survival of bacteria declined as the acid was increased from pH 7.5 to 4.5 at each time point. The bacteria can proliferate under each pH except pH 4.5 with time. The levels of sRNAs gradually decreased from pH 7.5 to 5.5, and slightly increased in pH 4.5; however, the expression levels of target mRNAs were up-regulated in acidic conditions than in pH 7.5. These results indicate that some sRNAs are specially induced at acid stress conditions, involving acid adaptation, and provide a new insight into exploring the complex acid tolerance for S. mutans., Competing Interests: The authors declare no conflict of interest.

Directed acyclic graphs (DAGs) are nonparametric graphical tools used to depict causal relations in the epidemiologic assessment of exposure-outcome associations. Although their use in dental research was first advocated in 2002, DAGs have yet to be widely adopted in this field. DAGs help identify threats to causal inference such as confounders, bias due to subject selection, and inappropriate handling of missing data. DAGs can also inform the data analysis strategy based on relations among variables depicted on it. This article uses the example of a study of temporomandibular disorders (TMDs), investigating causal effects of facial injury on subsequent risk of TMD. We illustrate how DAGs can be used to identify 1) potential confounders, 2) mediators and the consequences of attempt to estimate direct causal effects, 3) colliders and the consequences of conditioning on colliders, and 4) variables that are simultaneously mediators and confounders and the consequences of adjustment for such variables. For example, one DAG shows that statistical adjustment for the pressure pain threshold would necessarily bias the causal relation between facial injury and TMD. Finally, we discuss the usefulness of DAGs during study design, subject selection, and choosing variables to be measured in a study., (© International & American Associations for Dental Research 2016.)

Purpose: This article illustrates the process by which the Southwest Region of the National Dental Practice-Based Research Network (www.NationalDentalPBRN.org) fosters collaboration among practitioners and researchers in study concept development through protocol development groups (PODs). The Southwest Region begins this process by engaging PODs, which comprise dentists, hygienists, and/or academic faculty who share research interests related to improving dental care., Method: The PODs use the Tuckman four-stage model of group development (forming, storming, norming, and performing) to develop study concepts. This well-structured model encourages engagement among group members and enables quality discussion through organized sessions. This model provides milestones for the group's progression and for the members' interactions. The Southwest Region Directors play a crucial role in guiding and directing the development of PODs by aligning the members' research interests with the goals of the National Network., Results: POD engagement using Tuckman's stages has been successful in developing study concepts for submission to the National Network. Between 2012 and 2014, the Southwest Region has developed 14 PODs from 275 research ideas. Five of these study concepts have been submitted to the National Network for approval, including the Novel Tobacco Products POD, which showcases the applicability of Tuckman's model., Conclusion: Overall, the POD concept is a collaborative effort that brings together practitioners and academicians through shared research interests and capitalizes on participants' expertise and experiences. The Southwest Region will continue to develop PODs to foster new ideas for future studies in the Network., (© 2016 Society for Public Health Education.)

Objectives: To measure aspects of fizzy drink consumption in a social environment to inform the development of a laboratory testing regime., Methods: This was an observational study in which participants were invited to attend one of four pizza and soft drink parties. All such foods and drinks were served in an air conditioned room at a temperature of 24°C. All drinks were at a temperature of 4°C and each participant was asked to spit out, into graduated cups, their first and second sips. Both the temperature and volume of these were measured. Upon completion of the party the volume of drinks consumed was determined. Video footage of the experiment was recorded for subsequent analysis to determine sip count and the elapsed time period between first and last sip. These values were compared to the analogous measured value of expectorated volume in order to assess the usefulness of video observation in the context of this work., Results: The mean expectorated beverage temperature was 14.9±2.0°C. The mean time spent drinking was 44.2±17.4 minutes with a mean consumption rate of 13.3±6.0 ml/min. Only the sip volume and sip count per can values were significantly different between sexes (P<0.05) with females displaying lower values for volume and a higher sip count. There was close agreement between the sip volume values observed and calculated using video observation derived parameters., Conclusions: Several human drinking behaviour values were reported in this study and these will be of value in the development of more realistic laboratory erosion-testing regimes. It is concluded, within the limitations of this work, that (1) there are differences in the drinking behaviour of males and females with respect to sip volume and count, (2) the intraoral rise in temperature of a 4°C beverage is lower than that used in previous laboratory simulations and (3) the values derived from video observation agree with those measured directly validating this technique for use in further studies., Clinical Significance: The work provides valuable quantitative data on which to base simulated laboratory erosion work. Perhaps the most significant finding is that sipped beverages attain a temperature of only 14.9°C., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background and Overview: In everyday practice, dentists face clinical decisions for which they need to consider both treatment consequences (that is, benefits and harms) and costs. Economic analysis is a study design in which investigators evaluate and compare the costs and consequences of different treatment alternatives within a defined period. A critical appraisal of such studies includes an assessment of the risk of bias, results, and applicability of the study. The authors provide the concepts and guidelines that dentists can apply to critically appraise economic analyses., Practical Implications: Dentists who wish to inform their clinical decisions regarding questions that involve both treatment consequences and costs can use these guidelines to understand the different types of economic analyses and to decide what type of economic analyses to search for, as well as to critically appraise any economic analyses identified., (Copyright © 2015 American Dental Association. Published by Elsevier Inc. All rights reserved.)

Objectives: To assess the presence of within-group comparisons with baseline in a subset of leading dental journals and to explore possible associations with a range of study characteristics including journal and study design., Study Design and Setting: Thirty consecutive issues of five leading dental journals were electronically searched. The conduct and reporting of statistical analysis in respect of comparisons against baseline or otherwise along with the manner of interpretation of the results were assessed. Descriptive statistics were obtained, and chi-square test and Fisher's exact were undertaken to test the association between trial characteristics and overall study interpretation., Results: A total of 184 studies were included with the highest proportion published in Journal of Endodontics (n = 84, 46%) and most involving a single center (n = 157, 85%). Overall, 43 studies (23%) presented interpretation of their outcomes based solely on comparisons against baseline. Inappropriate use of baseline testing was found to be less likely in interventional studies (P < 0.001)., Conclusion: Use of comparisons with baseline appears to be common among both observational and interventional research studies in dentistry. Enhanced conduct and reporting of statistical tests are required to ensure that inferences from research studies are appropriate and informative., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Context: There is a need to evaluate the quality of postgraduate dissertations of dentistry submitted to university in the light of the international standards of reporting., Aims: We conducted the review with an objective to document the use of sampling methods, measurement standardization, blinding, methods to eliminate bias, appropriate use of statistical tests, appropriate use of data presentation in postgraduate dental research and suggest and recommend modifications., Settings and Design: The public access database of the dissertations from Rajiv Gandhi University of Health Sciences was reviewed., Subjects and Methods: Three hundred and thirty-three eligible dissertations underwent preliminary evaluation followed by detailed evaluation of 10% of randomly selected dissertations. The dissertations were assessed based on international reporting guidelines such as strengthening the reporting of observational studies in epidemiology (STROBE), consolidated standards of reporting trials (CONSORT), and other scholarly resources., Statistical Analysis Used: The data were compiled using MS Excel and SPSS 10.0. Numbers and percentages were used for describing the data., Results: The "in vitro" studies were the most common type of research (39%), followed by observational (32%) and experimental studies (29%). The disciplines conservative dentistry (92%) and prosthodontics (75%) reported high numbers of in vitro research. Disciplines oral surgery (80%) and periodontics (67%) had conducted experimental studies as a major share of their research. Lacunae in the studies included observational studies not following random sampling (70%), experimental studies not following random allocation (75%), not mentioning about blinding, confounding variables and calibrations in measurements, misrepresenting the data by inappropriate data presentation, errors in reporting probability values and not reporting confidence intervals. Few studies showed grossly inappropriate choice of statistical tests and many studies needed additional tests., Conclusions: Overall observations indicated the need to comply with standard guidelines of reporting research.

There is increasing importance placed on conducting clinical trials in dentistry to provide a robust evidence base for the treatment provided, and models of care delivered. However, providing the evidence upon which to base such decisions is not straightforward, as the conduct of these trials is complex. Currently, only limited information is available about the strategies to deliver successful clinical trials in primary care settings, and even less available on dental clinical trials. Considerable knowledge and experience is lost once a trial is completed as details about effective management of a trial are generally not reported or disseminated to trial managers and researchers. This leads to loss of vital knowledge that could assist with the effective delivery of new trials. The aim of this study is to examine the conduct and delivery of five dental clinical trials across both Australia and the UK and identify the various factors that impacted upon their implementation. Findings suggest that early stakeholder engagement, and well-designed and managed trials, lead to improved outcomes for researchers, clinic staff and patients, and increases the potential for future dissemination and translation of information into practice.

Missing outcome data are common in clinical trials and despite a well-designed study protocol, some of the randomized participants may leave the trial early without providing any or all of the data, or may be excluded after randomization. Premature discontinuation causes loss of information, potentially resulting in attrition bias leading to problems during interpretation of trial findings. The causes of information loss in a trial, known as mechanisms of missingness, may influence the credibility of the trial results. Analysis of trials with missing outcome data should ideally be handled with intention to treat (ITT) rather than per protocol (PP) analysis. However, true ITT analysis requires appropriate assumptions and imputation of missing data. Using a worked example from a published dental study, we highlight the key issues associated with missing outcome data in clinical trials, describe the most recognized approaches to handling missing outcome data, and explain the principles of ITT and PP analysis., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The practice of assessing must ensure that the outcome of the process be a reflection of the learning achieved by students. The aim of this study was to describe the essential attributes of the praxis teacher in the area of Endodontics Learning Evaluation, in the School of Dentistry at the Universidad de Concepción, Chile. This study is designed to diagnose the reliability and objectivity of assessing the learning process, as a framework for innovation, and with a focus on evaluating endodontics skills. This hermeneutic study has a qualitative methodology. It was based on in-depth semi-structured interviews applied to 14 students and 5 teachers, and two focus groups consisting of eight students each. When the study was conducted, the research findings indicated that the evaluation process was not objective and lacked established criteria, and especially a guide to determining the skills. The theoretical evaluation was only summative. The formative role was not formally established. The subjects answered mostly psychometric instruments by multiple choice and with short or extended answers. It was concluded that teacher practice held meaning only if it was backed by academic expertise in the area of endodontics, according to no clear criteria or validated instruments. On the other hand, the groundwork was in place for using an epistemological style in endodontics. This provided a basis for the actual improvements, and allowed the tools developed to be dialectically interconnected with teacher experience. A quantitative analysis was not considered, but could be supplemented later to enhance the data analysis in a future study.

Background: Split-mouth randomized controlled trials (RCTs) are popular in oral health research. Meta-analyses frequently include trials of both split-mouth and parallel-arm designs to derive combined intervention effects. However, carry-over effects may induce bias in split- mouth RCTs. We aimed to assess whether intervention effect estimates differ between split- mouth and parallel-arm RCTs investigating the same questions., Methods: We performed a meta-epidemiological study. We systematically reviewed meta- analyses including both split-mouth and parallel-arm RCTs with binary or continuous outcomes published up to February 2013. Two independent authors selected studies and extracted data. We used a two-step approach to quantify the differences between split-mouth and parallel-arm RCTs: for each meta-analysis. First, we derived ratios of odds ratios (ROR) for dichotomous data and differences in standardized mean differences (∆SMD) for continuous data; second, we pooled RORs or ∆SMDs across meta-analyses by random-effects meta-analysis models., Results: We selected 18 systematic reviews, for 15 meta-analyses with binary outcomes (28 split-mouth and 28 parallel-arm RCTs) and 19 meta-analyses with continuous outcomes (45 split-mouth and 48 parallel-arm RCTs). [corrected]. Effect estimates did not differ between split-mouth and parallel-arm RCTs (mean ROR, 0.96, 95% confidence interval 0.52-1.80; mean ∆SMD, 0.08, -0.14-0.30)., Conclusions: Our study did not provide sufficient evidence for a difference in intervention effect estimates derived from split-mouth and parallel-arm RCTs. Authors should consider including split-mouth RCTs in their meta-analyses with suitable and appropriate analysis.

Aims: To combine empirical evidence and expert opinion in a formal consensus method in order to develop a quality-assessment tool for experimental bruxism studies in systematic reviews., Methods: Tool development comprised five steps: (1) preliminary decisions, (2) item generation, (3) face-validity assessment, (4) reliability and discriminitive validity assessment, and (5) instrument refinement. The kappa value and phi-coefficient were calculated to assess inter-observer reliability and discriminative ability, respectively., Results: Following preliminary decisions and a literature review, a list of 52 items to be considered for inclusion in the tool was compiled. Eleven experts were invited to join a Delphi panel and 10 accepted. Four Delphi rounds reduced the preliminary tool-Quality-Assessment Tool for Experimental Bruxism Studies (Qu-ATEBS)- to 8 items: study aim, study sample, control condition or group, study design, experimental bruxism task, statistics, interpretation of results, and conflict of interest statement. Consensus among the Delphi panelists yielded good face validity. Inter-observer reliability was acceptable (k = 0.77). Discriminative validity was excellent (phi coefficient 1.0; P < .01). During refinement, 1 item (no. 8) was removed., Conclusion: Qu-ATEBS, the seven-item evidence-based quality assessment tool developed here for use in systematic reviews of experimental bruxism studies, exhibits face validity, excellent discriminative validity, and acceptable inter-observer reliability. Development of quality assessment tools for many other topics in the orofacial pain literature is needed and may follow the described procedure.

The following four fundamental points on the use of experimental models will be described to ensure an accurate evaluation of the effects of medication and laser therapy on induced tooth movement and associated root resorption: (1) If the objective is to check the effect on root resorption, the forces experimentally applied must produce a lesion on the cementoblast layer in all specimens; (2) If the objective is to optimize induced tooth movement and reduce treatment time without side effects, the forces experimentally applied should not produce a lesion in the cementoblast layer in any specimen; (3) The laser therapy operator, the person administering medication and the person that places appliances should not know which animals will effectively receive the test treatment, and the control groups should receive placebo treatments; (4) CT and microscopic analysis of the specimens should be random, and the group to which the specimen belongs should not be identified, to ensure that the person reading images and the pathologists are not influenced in their evaluation of phenomena. These measures will ensure that results are more reliable and easier to extrapolate to orthodontic clinical practice.

Objective: To evaluate the effectiveness of a new journal-based learning (JBL) programme designed to equip students with skills necessary to understand dental research publications, thereby preparing them for continuing professional development., Materials and Methods: A baseline evaluation of knowledge relating to key research terms was conducted on 52 final-year BDS students. 11 weekly seminars were conducted from 8 clinical disciplines driven by a reading list of 2-5 journal articles along with a series of 'guidance' questions relating to research terms and content knowledge aspects of each paper to focus their reading and learning. Seminars were facilitated by discipline experts with supporting notes. An exit test based on research process and terminologies for the programme was conducted with 4 repeated questions from the baseline assessment. A systematic marking scheme was used and the results analysed. A focus group was run to collect feedback regarding students' views and experiences on the JBL experience., Findings: Students showed significant improvements over the baseline score. The mean score rose from 3.5 to 11.5 in the repeated questions (P < 0.001). The focus group revealed that students had learnt new information about journal classification, evidence level determination, new research terms and the structure of research papers. From the first 4 years of PBL, students recognized the importance of learning from research papers since year 1. However, JBL gave them a deeper understanding of research and the development of critical appraisal skills., Implications: JBL provided final-year students the opportunity to learn significantly more about dental research, terminologies, paper structure, critical analysis and content knowledge through active-learning small group seminars., (© 2012 John Wiley & Sons A/S.)

Population-level research is an essential area of health with the potential to affect quality of life and the broader economy. There are excellent epidemiological studies that have improved health services, but traditional research requires a considerable investment. Although electronic technology has changed the practice of many industries with improved efficiency, its application to health is relatively new. Termed 'e-health', this emerging area has been defined by the World Health Organization as the use of information technology to support many aspects of health such as in administration and scientific information. However, not all professionals are convinced of its use. This paper presents a novel application of this emerging area to describe the benefit in data collation and research to support one of the most pressing issues in public health: oral health and policy. Using the Chronic Disease Dental Scheme as an example, a critical discussion of its benefit to population-level research is presented. The Chronic Disease Dental Scheme method of electronic administration has been shown to enhance research and to complement existing progress in health data linkage. e-Health is an invaluable tool for population-level dental research.

Dental adhesive systems should provide a variety of capabilities, such as bonding of artificial materials to dentin and enamel, sealing of dentinal tubules, reduction of post-operative sensitivity and marginal sealing to reduce marginal staining and caries. In the laboratory, numerous surrogate parameters that should predict the performance of different materials, material combinations and operative techniques are assessed. These surrogate parameters include bond strength tests of various kinds, evaluation of microleakage with tracer penetration between restorative and tooth, two-dimensional analysis of marginal quality with microscopes and mapping of the micromorphology of the bonding interface. Many of these tests are not systematically validated and show therefore different results between different research institutes. The correlation with clinical phenomena has only partly been established to date. There is some evidence, that macrotensile and microtensile bond strength tests correlate better with clinical retention of cervical restorations than macroshear and microshear bond tests but only if data from different test institutes are pooled. Also there is some evidence that marginal adaptation has a moderate correlation in cervical restorations with clinical retention and in Class II restorations (proximal enamel) with clinical marginal staining. There is moderate evidence that microleakage tests with dye penetration does not correlate with any of the clinical parameters (post-operative hypersensitivity, retention, marginal staining). A rationale which helps the researcher to select and apply clinically relevant test methods in the laboratory is presented in the paper., (Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.)

The rodent model of dental caries has made fundamental contributions to the understanding of the etiology, pathogenesis, and prevention of this disease. In conducting animal-based investigations, important details considered essential for successful outcome are occasionally overlooked. Adequate number of animals of appropriate age should always be included to ensure sufficient statistical power to draw valid conclusions. Attention should be paid to litter source as it is clear that litter origin may have a profound effect on the outcome. Inclusion of additive in diet may also affect eating pattern. A range of special techniques are available which can expand the role of animals in exploring the pathogenesis of dental caries. The arrival of genetically altered microorganisms along with availability of knock-out rodents offers exciting challenges to further explore the pathogenesis of this still too common disease.

Introduction: This article reports on the feasibility of conducting a large-scale endodontic prospective cohort study in The National Dental Practice-Based Research Network. This study was designed to measure pain and burden associated with initial orthograde root canal therapy (RCT) and to explore potential prognostic factors for pain outcomes. The main objectives of this first report in a series are to describe the project's feasibility and methods and the demographics of the sample obtained., Methods: Sixty-two dentist practitioner-investigators (ie, 46 generalists and 16 endodontists) in 5 geographic areas were certified within the network and trained regarding the standardized study protocol. Enrollment and baseline data collection occurred over 6 months with postobturation follow-up for another 6 months. Patients and dentists completed questionnaires before and immediately after treatment visits. Patients also completed questionnaires at 1 week, 3 months, and 6 months after obturation., Results: Enrollment exceeded target expectations, with 708 eligible patient-participants. Questionnaire return rates were good, ranging between 90% and 100%. Patient demographics were typical of persons who receive RCT in the United States (ie, mean age = 48 years [standard deviation = 13 years], with most being female [59%], college educated [81%], white non-Hispanic [86%], and having dental insurance [81%]). The tooth types being treated were also typical (ie, 61% molars, 28% premolars, and 11% anteriors, with maxillary teeth being predominant [59%])., Conclusions: This study shows the feasibility of conducting large-scale endodontic prospective cohort studies in the network. Patients were rapidly recruited with high levels of compliance in data collection., (Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)