21 resultados para dissertation abstracts

em BORIS: Bern Open Repository and Information System - Berna - Suiça


Relevância:

60.00% 60.00%

Publicador:

Resumo:

INTRODUCTION Light cure of resin-based adhesives is the mainstay of orthodontic bonding. In recent years, alternatives to conventional halogen lights offering reduced curing time and the potential for lower attachment failure rates have emerged. The relative merits of curing lights in current use, including halogen-based lamps, light-emitting diodes (LEDs), and plasma arc lights, have not been analyzed systematically. In this study, we reviewed randomized controlled trials and controlled clinical trials to assess the risks of attachment failure and bonding time in orthodontic patients in whom brackets were cured with halogen lights, LEDs, or plasma arc systems. METHODS Multiple electronic database searches were undertaken, including MEDLINE, EMBASE, and the Cochrane Oral Health Group's Trials Register, CENTRAL. Language restrictions were not applied. Unpublished literature was searched on ClinicalTrials.gov, the National Research Register, Pro-Quest Dissertation Abstracts, and Thesis database. Search terms included randomized controlled trial, controlled clinical trial, random allocation, double blind method, single blind method, orthodontics, LED, halogen, bond, and bracket. Authors of primary studies were contacted as required, and reference lists of the included studies were screened. RESULTS Randomized controlled trials and clinical controlled trials directly comparing conventional halogen lights, LEDs, or plasma arc systems involving patients with full arch, fixed, or bonded orthodontic appliances (not banded) with follow-up periods of a minimum of 6 months were included. Using predefined forms, 2 authors undertook independent extraction of articles; disagreements were resolved by discussion. The assessment of the risk of bias of the randomized controlled trials was based on the Cochrane Risk of Bias tool. Ten studies met the inclusion criteria; 2 were excluded because of high risk of bias. In the comparison of bond failure risk with halogen lights and plasma arc lights, 1851 brackets were included in both groups. Little statistical heterogeneity was observed in this analysis (I(2) = 4.8%; P = 0.379). There was no statistical difference in bond failure risk between the groups (OR, 0.92; 95% CI, 0.68-1.23; prediction intervals, 0.54, 1.56). Similarly, no statistical difference in bond failure risk was observed in the meta-analysis comparing halogen lights and LEDs (OR, 0.96; 95% CI, 0.64-1.44; prediction intervals, 0.07, 13.32). The pooled estimates from both comparisons were OR, 0.93; 95% CI, 0.74-1.17; and prediction intervals, 0.69, 1.17. CONCLUSIONS There is no evidence to support the use of 1 light cure type over another based on risk of attachment failure.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

INTRODUCTION The objective of this systematic review was to assess the short- and long-term release of components of orthodontic adhesives and polycarbonate brackets in the oral environment. METHODS Electronic database searches of published and unpublished literature were performed. The following electronic databases with no language and publication date restrictions were searched: MEDLINE (via Ovid and PubMed), EMBASE (via Ovid), Cochrane Oral Health Group's Trials Register, and CENTRAL. Unpublished literature was searched on ClinicalTrials.gov, the National Research Register, and Pro-Quest Dissertation Abstracts and Thesis database. The reference lists of all eligible studies were checked for additional studies. Two review authors performed data extraction independently and in duplicate using data collection forms. Disagreements were resolved by discussion or the involvement of an arbiter. RESULTS No randomized controlled trial was identified. In the absence of randomized controlled trials, observational studies were included. Eleven studies met the inclusion criteria. All were observational studies conducted in vivo or in vitro. The bisphenol-A release from orthodontic bonding resins was found to be between 0.85 and 20.88 ng per milliliter in vivo, and from traces to 65.67 ppm in vitro. Polycarbonate brackets released amounts of 22.24 μg per gram in ethanol solution and 697 μg per gram after 40 months in water. Bis-GMA and TEGDMA leaching in vitro reached levels of 64 and 174 mg per 10 μL, respectively. Because of the heterogeneity in methodologies and reporting, only qualitative synthesis was performed. CONCLUSIONS The available evidence on this topic derived from observational in-vivo and in-vitro studies that represent a moderate level of evidence. The variety of setups and the different units allied to the diversity of reporting among studies did not allow calculation of pooled estimates.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

PURPOSE To analyze available evidence on the incidence of anatomical variations or disease of the maxillary sinuses as identified by cone beam computed tomography (CBCT) in dentistry. MATERIALS AND METHODS A focused question was developed to search the electronic databases MEDLINE, EMBASE, the Cochrane Oral Health Group Trials Register, and CENTRAL and identify all relevant papers published between 1980 and January 19, 2013. Unpublished literature at ClinicalTrials.gov, in the National Research Register, and in the Pro-Quest Dissertation Abstracts and Thesis database was also included. Studies were included irrespective of language. These results were supplemented by hand and gray literature searches. RESULTS Twenty-two studies were identified. Twenty were retrospective cohort studies, one was a prospective cohort study, and one was a case control study. The main indication for CBCT was dental implant treatment planning, and the majority of studies used a small field of view for imaging. The most common anatomical variations included increased thickness of the sinus membrane, the presence of sinus septa, and pneumatization. Reported sinus disease frequency varied widely, ranging from 14.3% to 82%. There was a wide range in the reported prevalence of mucosal thickening related to apical pathology, the degree of lumenal opacification, features of sinusitis, and the presence of retention cysts and polyps. More pathologic findings in the maxillary sinus were reported in men than in women, and the medial wall and sinus floor were most frequently affected. CONCLUSION CBCT is used primarily to evaluate bony anatomy and to screen for overt pathology of the maxillary sinuses prior to dental implant treatment. Differences in the classification of mucosal findings are problematic in the consistent and valid assessment of health and disease of the maxillary sinus.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

AIM To systematically search the literature and assess the available evidence for the influence of chin-cup therapy on the temporomandibular joint regarding morphological adaptations and appearance of temporomandibular disorders (TMD). MATERIALS AND METHODS Electronic database searches of published and unpublished literature were performed. The following electronic databases with no language and publication date restrictions were searched: MEDLINE (via Ovid and PubMed), EMBASE (via Ovid), the Cochrane Oral Health Group's Trials Register, and CENTRAL. Unpublished literature was searched on ClinicalTrials.gov, the National Research Register, and Pro-Quest Dissertation Abstracts and Thesis database. The reference lists of all eligible studies were checked for additional studies. Two review authors performed data extraction independently and in duplicate using data collection forms. Disagreements were resolved by discussion or the involvement of an arbiter. RESULTS From the 209 articles identified, 55 papers were considered eligible for inclusion in the review. Following the full text reading stage, 12 studies qualified for the final review analysis. No randomized clinical trial was identified. Eight of the included studies were of prospective and four of retrospective design. All studies were assessed for their quality and graded eventually from low to medium level of evidence. Based on the reported evidence, chin-cup therapy affects the condylar growth pattern, even though two studies reported no significance changes in disc position and arthrosis configuration. Concerning the incidence of TMD, it can be concluded from the available evidence that chin-cup therapy constitutes no risk factor for TMD. CONCLUSION Based on the available evidence, chin-cup therapy for Class III orthodontic anomaly seems to induce craniofacial adaptations. Nevertheless, there are insufficient or low-quality data in the orthodontic literature to allow the formulation of clear statements regarding the influence of chin-cup treatment on the temporomandibular joint.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Optimal reporting of randomized trials and abstracts enhances transparency and facilitates assessment and identification of trials. The purpose of this study was to investigate the quality of reporting of abstracts of randomized controlled trials published in orthodontic journals.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

BACKGROUND: Abstracts of presentations at scientific meetings are usually available only in conference proceedings. If subsequent full publication of abstract results is based on the magnitude or direction of study results, publication bias may result. Publication bias, in turn, creates problems for those conducting systematic reviews or relying on the published literature for evidence. OBJECTIVES: To determine the rate at which abstract results are subsequently published in full, and the time between meeting presentation and full publication. To assess the association between study characteristics and full publication. SEARCH STRATEGY: We searched MEDLINE, EMBASE, The Cochrane Library, Science Citation Index, reference lists, and author files. Date of most recent search: June 2003. SELECTION CRITERIA: We included all reports that examined the subsequent full publication rate of biomedical results initially presented as abstracts or in summary form. Follow-up of abstracts had to be at least two years. DATA COLLECTION AND ANALYSIS: Two reviewers extracted data. We calculated the weighted mean full publication rate and time to full publication. Dichotomous variables were analyzed using relative risk and random effects models. We assessed time to publication using Kaplan-Meier survival analyses. MAIN RESULTS: Combining data from 79 reports (29,729 abstracts) resulted in a weighted mean full publication rate of 44.5% (95% confidence interval (CI) 43.9 to 45.1). Survival analyses resulted in an estimated publication rate at 9 years of 52.6% for all studies, 63.1% for randomized or controlled clinical trials, and 49.3% for other types of study designs.'Positive' results defined as any 'significant' result showed an association with full publication (RR = 1.30; CI 1.14 to 1.47), as did 'positive' results defined as a result favoring the experimental treatment (RR =1.17; CI 1.02 to 1.35), and 'positive' results emanating from randomized or controlled clinical trials (RR = 1.18, CI 1.07 to 1.30).Other factors associated with full publication include oral presentation (RR = 1.28; CI 1.09 to 1.49); acceptance for meeting presentation (RR = 1.78; CI 1.50 to 2.12); randomized trial study design (RR = 1.24; CI 1.14 to 1.36); and basic research (RR = 0.79; CI 0.70 to 0.89). Higher quality of abstracts describing randomized or controlled clinical trials was also associated with full publication (RR = 1.30, CI 1.00 to 1.71). AUTHORS' CONCLUSIONS: Only 63% of results from abstracts describing randomized or controlled clinical trials are published in full. 'Positive' results were more frequently published than not 'positive' results.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Sportliche Aktivitäten sind in vielfältiger Art und Weise in sozial strukturierte Handlungssituationen eingebettet und institutionalisiert. Dabei sind soziale Strukturen des Sports in Form von Regeln, Normen, Werten und Rollen für das sportliche Handeln von wichtiger Bedeutung. Vor diesem Hintergrund stellen sich folgende Fragen aus unterschiedlichen Perspektiven: Wie erwerben Menschen im Sport soziale Handlungsfähigkeit und Rollensicherheit, die sozial konformes und gleichzeitig eigenständiges Handeln ermöglichen? Inwieweit lassen sich die im Sport erworbenen sozialen Kompetenzen, Handlungsorientierungen und Werte auch auf andere Bereiche übertragen? Von welchen sozialen Faktoren ist der Zugang zu gruppenbezogenen Sportaktivitäten abhängig? Der vorliegende Tagungsband enthält alle Abstracts zu den Hauptvorträgen sowie den Vorträgen aus den Arbeitskreisen der Jahrestagung der dvs-Sektion Sportsoziologie in Kooperation mit der Sektion Sportpädagogik, die vom 17.-19. September 2008 in Chemnitz stattfand. Der Band gibt damit einen umfassenden Überblick zur aktuellen Diskussion der sportbezogenen Sozialisationsforschung.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

OBJECTIVES Abstracts of systematic reviews are of critical importance, as consumers of research often do not access the full text. This study aimed to assess the reporting quality of systematic review (SR) abstracts in leading oral implantology journals. METHODS Six specialty journals were screened for SRs between 2008 and 2012. A 16-item checklist, based on the PRISMA statement, was used to examine the completeness of abstract reporting. RESULTS Ninety-three SR abstracts were included in this study. The majority were published in Clinical Oral Implants Research (43%). The mean overall reporting quality score was 72.5% (95% CI: 70.8-74.2). Most abstracts were structured (97.9%), adequately reporting objectives (97.9%) and conclusions (93.6%). Conversely, inadequate reporting of methods of the study, background (79.6%), appraisal (65.6%), and data synthesis (65.6%) were observed. Registration of reviews was not reported in any of the included abstracts. Multivariate analysis revealed no difference in reporting quality with respect to continent, number of authors, or meta-analysis conduct. CONCLUSIONS The results of this study suggest that the reporting quality of systematic review abstracts in implantology journals requires further improvement. CLINICAL SIGNIFICANCE Better reporting of SR abstracts is particularly important in ensuring the reliability of research findings, ultimately promoting the practice of evidence-based dentistry. Optimal reporting of SR abstracts should be encouraged, preferably by endorsing the PRISMA for abstracts guidelines.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aim of this study was to investigate the reporting completeness of systematic review (SR) abstracts in leading dental specialty journals. Electronic and supplementary hand searching were undertaken to identify SRs published in seven dental specialty journals and in the Cochrane Database of Systematic Reviews. Abstract reporting completeness was evaluated using a checklist derived from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (prisma) guidelines. Descriptive statistics followed by univariate and multivariate analyses were conducted. Two-hundred and eighteen SR abstracts were identified. Reporting of interventions (94%), objectives (96%), data sources (81%), eligibility criteria (77%), and conclusions (97%) was adequate in the majority of reviews. However, inadequate reporting of participants (18%), results (42%), effect size (14%), level of significance (60%), and trial registration (100%) was commonplace. The mean overall reporting score was 79.1% (95% CI, 77.6-80.6). Only journal of publication was a significant predictor of overall reporting, with inferior results for all journals relative to Cochrane reviews, with scores ranging from -4.3% (95% CI, -8.74 to 0.08) to -35.6% (95% CI, -42.0 to -24.3) for the International Journal of Prosthodontics and the British Journal of Oral and Maxillofacial Surgery, respectively. Improved reporting of dental SR abstracts is needed and should be encouraged, as these abstracts may underpin influential clinical decisions.