The Influence of Contemporary Denture Base Fabrication Methods on Residual Monomer Content, Flexural Strength and Microhardness

(1) Background: Digital technologies are available for denture base fabrication, but there is a lack of scientific data on the mechanical and chemical properties of the materials produced in this way. Therefore, the aim of this study was to investigate the residual monomer content, flexural strength and microhardness of denture base materials as well as correlations between investigated parameters. (2) Methods: Seven denture base materials were used: one conventional heat cured polymethyl methacrylate, one polyamide, three subtractive manufactured materials and two additive manufactured materials. High-performance liquid chromatography was used to determine residual monomer content and the test was carried out in accordance with the specification ISO No. 20795-1:2013. Flexural strength was also determined according to the specification ISO No. 20795-1:2013. The Vickers method was used to investigate microhardness. A one-way ANOVA with a Bonferroni post-hoc test was used for the statistical analysis. The Pearson correlation test was used for the correlation analysis. (3) Results: There was a statistically significant difference between the values of residual monomer content of the different denture base materials (p p p p < 0.05). (4) Conclusions: The selection of contemporary digital denture base manufacturing techniques may affect residual monomer content, flexural strength and microhardness but is not the only criterion for achieving favourable properties

Oral Hygiene Practices and Oral Health Knowledge among Adult Orthodontic Patients: A Best Practice Implementation Project

Orthodontic therapy is associated with a more significant accumulation of dentobacterial plaque and impaired oral hygiene, which increase the risk of developing dental caries and periodontal disease. Therefore, it is crucial to educate orthodontic patients about proper oral hygiene maintenance and oral health before and during treatment. The aim of this pilot study was to implement evidence-based best practices related to oral hygiene in adult orthodontic patients and improve compliance. In addition to evaluating oral hygiene practices, another goal of the project was to assess the knowledge of orthodontic patients regarding oral health. Questionnaires with seven pre- (before) and post-test criteria (90 day after implementation) were developed based on the best evidence available. This project was conducted in a private dental clinic in Split, Croatia, and included 45 patients. The baseline audit showed a gap between clinical practice and the best evidence. Three criteria achieved a high compliance baseline, while after implementation, there were substantial improvements in compliance for all. The everyday use of mouthwash improved from 17.8% at baseline to 66.7% at follow-up, as did the use of interdental aids, which increased from 55.6% to 91.1%. Statistically significant differences were found in the total score for oral health knowledge between the baseline (6.67 ± 1.74) and the follow-up audit (7.78 ± 0.56, p ≤ 0.001). The strategies developed in this project were effective in providing essential information to adult orthodontic patients and improving compliance with evidence. Guidelines on this topic should be designed to assist orthodontists and patients in maintaining oral health and oral hygiene

The judgement of biases included in the category “other bias” in Cochrane systematic reviews of interventions: a systematic survey

Abstract Background Clinical decisions are made based on Cochrane reviews, but the implementation of results of evidence syntheses such as Cochrane reviews is problematic if the evidence is not prepared consistently. All systematic reviews should assess the risk of bias (RoB) in included studies, and in Cochrane reviews, this is done by using Cochrane RoB tool. However, the tool is not necessarily applied according to the instructions. In this study, we aimed to determine the types of bias and their corresponding judgements noted in the ‘other bias’ domain of Cochrane RoB tool. Methods We analyzed Cochrane reviews that included randomized controlled trials (RCTs) and extracted data regarding ‘other bias’ from the RoB table and accompanying support for the judgment. We categorized different types of other bias. Results We analyzed 768 Cochrane reviews that included 11,369 RCTs. There were 602 (78%) Cochrane reviews that had ‘other bias’ domain in the RoB tool, and they included a total of 7811 RCTs. In the RoB table of 337 Cochrane reviews for at least one of the included trials it was indicated that no other bias was found and supporting explanations were inconsistently judged as low, unclear or high RoB. In the 524 Cochrane reviews that described various sources of other bias, there were 5762 individual types of explanations which we categorized into 31 groups. The judgments of the same supporting explanations were highly inconsistent. We found numerous other inconsistencies in reporting of sources of other bias in Cochrane reviews. Conclusion Cochrane authors mention a wide range of sources of other bias in the RoB tool and they inconsistently judge the same supporting explanations. Inconsistency in appraising risk of other bias hinders reliability and comparability of Cochrane systematic reviews. Discrepant and erroneous judgments of bias in evidence synthesis may hinder implementation of evidence in routine clinical practice and reduce confidence in otherwise trustworthy sources of information. These results can help authors of Cochrane and non-Cochrane reviews to gain insight into various sources of other bias that can be found in trials, and also to help them avoid mistakes that were recognized in published Cochrane reviews

Clinical use of ivabradine in the acute coronary syndrome: A systematic review and narrative synthesis of current evidence

Heart rate (HR) lowering during acute coronary syndrome (ACS) is beneficial as it reduces myocardial oxygen consumption. However, the role of ivabradine as an HR-lowering agent in the setting of ACS is not clear. We aimed to systematically review and synthesize the current evidence on the role of ivabradine use in the ACS. A systematic review was conducted for eligible randomized clinical trials and quasi-experimental studies, between 2009 and 2020, that investigated the use of ivabradine in ACS. Various clinical endpoints were evaluated such as major adverse cardiovascular events, efficacy in HR control, impact on left ventricular (LV) dimensions and function, and overall safety. Eleven publications were included encompassing a total of 1833 patients. The mean age of the examined cohort was 57 +/- 11 years and 80 % were men. Seven studies were in the setting of STsegment elevation myocardial infarction (MI) while the remaining studies also included patients with unstable angina and non-ST-segment elevation MI. Ivabradine was administered as a peroral drug with dosing from 2.5 to 7.5 mg b.i.d. Overall, the addition of ivabradine was superior to the control arm concerning HR control with a good safety profile. Beneficial effects on LV function and potential impact on infarct size reduction were observed as well. The use of ivabradine appeared to not affect short-term mortality. In conclusion, the use of ivabradine for HR control is safe, feasible, and efficacious for HR control in the ACS. Further studies are required to elucidate other potentially beneficial effects of ivabradine

Assessments of attrition bias in Cochrane systematic reviews are highly inconsistent and thus hindering trial comparability

Abstract Background An important part of the systematic review methodology is appraisal of the risk of bias in included studies. Cochrane systematic reviews are considered golden standard regarding systematic review methodology, but Cochrane’s instructions for assessing risk of attrition bias are vague, which may lead to inconsistencies in authors’ assessments. The aim of this study was to analyze consistency of judgments and support for judgments of attrition bias in Cochrane reviews of interventions published in the Cochrane Database of Systematic Reviews (CDSR). Methods We analyzed Cochrane reviews published from July 2015 to June 2016 in the CDSR. We extracted data on number of included trials, judgment of attrition risk of bias for each included trial (low, unclear or high) and accompanying support for the judgment (supporting explanation). We also assessed how many Cochrane reviews had different judgments for the same supporting explanations. Results In the main analysis we included 10,292 judgments and supporting explanations for attrition bias from 729 Cochrane reviews. We categorized supporting explanations for those judgments into four categories and we found that most of the supporting explanations were unclear. Numerical indicators for percent of attrition, as well as statistics related to attrition were judged very differently. One third of Cochrane review authors had more than one category of supporting explanation; some had up to four different categories. Inconsistencies were found even with the number of judgments, names of risk of bias domains and different judgments for the same supporting explanations in the same Cochrane review. Conclusion We found very high inconsistency in methods of appraising risk of attrition bias in recent Cochrane reviews. Systematic review authors need clear guidance about different categories they should assess and judgments for those explanations. Clear instructions about appraising risk of attrition bias will improve reliability of the Cochrane’s risk of bias tool, help authors in making decisions about risk of bias and help in making reliable decisions in healthcare

AMSTAR 2 is only partially applicable to systematic reviews of non-intervention studies : a meta-research study

Objectives: A measurement tool to assess systematic reviews 2 (AMSTAR 2) was originally developed for systematic reviews (SRs) of health-care interventions. The aim of this study was to assess the applicability of AMSTAR 2 to SRs of non-intervention studies. Study design and setting: This was a meta-research study. We used 20 SRs for each of the following four types of SRs: Diagnostic Test Accuracy reviews, Etiology and/or Risk reviews, Prevalence and/or Incidence reviews, and Prognostic reviews (80 in total). Three authors applied AMSTAR 2 independently to each included SRs. Then, the authors assessed the applicability of each item to that SR type and any SR type. Results: Researchers unanimously indicated that 7 of 16 AMSTAR 2 items were applicable for all four specific SR types and any SR type (items 2, 5, 6, 7, 10, 14 and 16), but 8 of 16 items for any SR type. These items could cover generic SR methods that do not depend on a specific SR type. Conclusion: AMSTAR 2 is only partially applicable for non-intervention SRs. There is a need to adapt/extend AMSTAR 2 for SRs of non-intervention studies. Our study can help to further define generic methodological aspects shared across SR types and methodological expectations for non-intervention SRs