Influence of thermal stress on marginal integrity of restorative materials

The aim of this study was to evaluate the influence of thermal stress on the marginal integrity of restorative materials with different adhesive and thermal properties. Three hundred and sixty Class V cavities were prepared in buccal and lingual surfaces of 180 bovine incisors. Cervical and incisal walls were located in dentin and enamel, respectively. Specimens were restored with resin composite (RC); glass ionomer (GI) or amalgam (AM), and randomly assigned to 18 groups (n=20) according to the material, number of cycles (500 or 1,000 cycles) and dwell time (30 s or 60 s). Dry and wet specimens served as controls Specimens were immersed in 1% basic fuchsine solution (24 h), sectioned, and microleakage was evaluated under x40 magnification. Data were analyzed by Kruskal-Wallis and Mann-Whitney tests: Thermal cycling regimens increased leakage in all AM restorations (

Adherence to preprints’ publication in Dentistry by Brazilian researchers

Aim: The publication in preprint format is an interesting open science practice that allows fast outreach to the society of new scientific findings. However, no previous study has investigated how much this practice has been adopted by dental scientists. Therefore, the objective of this study was to evaluate the adherence to the preprint publication format by a sample of Brazilian researchers. Methods: Searches were carried out, in September 2021, on the MedArxiv, OSF, and SciELO preprints platforms, looking for publications in preprint format by all Brazilian researchers of graduate programs in dentistry (n=211) who were productivity fellows in 2021 (PQ). Searches were performed by typing the authors’ full names and the possible variations, as indicated by each author's curriculum, openly available on the Lattes website platform. The data were analyzed through the Friedman test, with the Durbin-Conover post-hoc (α=0.05) in order to compare the three platforms. Spearman's correlation test (α=0.05) was performed to assess the possible correlations between the number of preprints and age, career stage, and the researcher’s scholarship level variables. Results: From the 211 researchers searched, 22 (10.4%) published 1 (one) preprint on at least one platform. A total of 39 published preprints were found at MedArxiv (n=19, 48.7%), SciELO preprints (n=18, 46.2%), and OSF platforms (n=2, 5.1%). There was no difference between the adherence to MedArxiv and SciELO preprints (p = 0.731). However, the OSF platform presented the lowest adherence, statistically differing from MedArxiv (p=0.008) and SciELO preprints platforms (p=0.003). In addition, no correlation was found between the publication of preprints and the researcher's age (p=0.128), career stage (p=0.248), or the researcher's scholarship level (p=0.661). Conclusion: It was possible to observe a low adherence to the preprints publications by Brazilian researchers’ productivity fellows of graduate programs in dentistry

Adesão ao formato preprint por docentes de odontologia das universidades públicas do Rio Grande do Sul

Aim: To evaluate the adherence to the publication of preprints by professors of postgraduate programs in Dentistry, from the three Federal Universities of the Rio Grande do Sul (UFRGS, UFPel and UFSM) (n = 97). Materials and methods: Four reviewers performed a search for publications in the preprint format, in May 2021, on the MedArxiv and SciELO Preprints platforms, for each included professor. The same reviewers extracted the data which were checked by a fifth reviewer. Fisher's exact test was used for the evaluation and comparison of the different universities. For comparison between platforms, Pearson's Chi-square test was applied with α = 0.05. Results: The results showed that 16.5% (n=16) of the total number of professors included had already published at least 1 preprint on either of the platforms, with UFPel differing statistically from the other universities, with the highest membership followed by UFRGS and UFSM (p = 0.038). There was no statistical difference between the platforms concerning the number of published preprints (p=0,306). Discussion: The findings demonstrate that this format, even incipiently, is already a reality in the Dentistry field. Conclusion: The findings of this study indicate a low rate of adherence to the preprint publication model by professors of the postgraduate programs in Dentistry in the public universities in of the Rio Grande do Sul state in Brazil.Objetivo: Avaliar a aderência à publicação de preprints pelos professores dos cursos de pós-graduação em Odontologia, das três Universidades Federais do Estado do Rio Grande do Sul (UFRGS, UFPel e UFSM) (n = 97). Materiais e métodos: Quatro revisores realizaram a busca de publicações em formato preprint, em maio de 2021, nas plataformas MedArxiv e SciELO Preprints, por cada professor incluído. Os mesmos revisores extraíram os dados que foram checados por um quinto revisor. Para a avaliação e comparação das diferentes universidades foi utilizado o teste exato de Fisher, com posterior análise dos resíduos com α corrigido. Para a comparação entre as plataformas foi realizado o teste do Qui-quadrado de Pearson (α = 0,05). Resultados: Os resultados mostraram que 16,5% (n=16) do total de professores incluídos já haviam publicado pelo menos 1 preprint em alguma das duas plataformas, sendo que a UFPel diferiu estatisticamente das outras universidades, apresentando o maior número de aderência seguido pela UFRGS e UFSM (p=0,038). Não houve diferença estatística quanto a comparação das plataformas pesquisadas (p=0,306). Discussão: Os achados demonstram que este formato, mesmo que de forma incipiente, já é uma realidade na área de Odontologia. Conclusão: Os achados deste estudo indicam uma baixa taxa de aderência ao formato de publicação preprint pelos professores dos programas de pós-graduação em Odontologia das universidades públicas do Rio Grande do Sul

Influence of caries activity and number of saliva donors: mineral and microbiological responses in a microcosm biofilm model

Objective: this study evaluated the mineral and microbiological response of biofilms originating from different types of saliva inoculum with distinct levels of caries activity. Methodology: the biofilms grown over enamel specimens originated from saliva collected from a single donor or five donors with two distinct levels of caries activity (caries-active and caries-free) or from pooling saliva from ten donors (five caries-active and five caries-free). The percentage surface hardness change (%SHC) and microbiological counts served as outcome variables. Results: the caries activity of donors did not affect the %SHC values. Inoculum from five donors compared to a single donor showed higher %SHC values (p=0.019). Higher lactobacilli counts were observed when saliva from caries-active donors was used as the inoculum (p=0.017). Pooled saliva from both caries activity levels showed higher mutans streptococci counts (p<0.017). Conclusion: Overall, pooled saliva increased the mineral response of the derived biofilms, but all the inoculum conditions formed cariogenic biofilms and caries lesions independently of caries activity

Influence of caries activity and number of saliva donors : mineral and microbiological responses in a microcosm biofilm model

Objective: this study evaluated the mineral and microbiological response of biofilms originating from different types of saliva inoculum with distinct levels of caries activity. Methodology: the biofilms grown over enamel specimens originated from saliva collected from a single donor or five donors with two distinct levels of caries activity (caries-active and caries-free) or from pooling saliva from ten donors (five caries-active and five caries-free). The percentage surface hardness change (%SHC) and microbiological counts served as outcome variables. Results: the caries activity of donors did not affect the %SHC values. Inoculum from five donors compared to a single donor showed higher %SHC values (p=0.019). Higher lactobacilli counts were observed when saliva from caries-active donors was used as the inoculum (p=0.017). Pooled saliva from both caries activity levels showed higher mutans streptococci counts (p<0.017). Conclusion: Overall, pooled saliva increased the mineral response of the derived biofilms, but all the inoculum conditions formed cariogenic biofilms and caries lesions independently of caries activity

Triple-blinded randomized clinical trial comparing efficacy and tooth sensitivity of in-office and at-home bleaching techniques

Objective: Our study aims to compare the efficacy and tooth sensitivity following in-office (35% hydrogen peroxide) or at-home (10% carbamide peroxide) bleaching treatments both preceded by 2% potassium nitrate (2%KF) desensitizing gel. Methodology: 130 volunteers were randomly allocated to a) in-office bleaching and a placebo at-home protocol; or b) in-office placebo and at-home bleaching treatment. 2% KF was applied for 10 min before both treatments. Objective: color evaluation was performed (spectrophotometer CIEL*a*b* system and CIEDE2000) to calculate the color change (ΔE00). Subjective evaluation was performed using the VITA classical shade guide followed by shade variation (ΔSGU) at the beginning and end of bleaching treatment and 2 weeks post-bleaching. Tooth sensitivity was daily recorded using a Likert scale varying from 1 (no sensitivity) to 5 (severe sensitivity). Analysis was carried out using non-parametric tests. Results: Regarding the color change, at-home bleaching resulted in significant color improvement compared to in-office treatment for the parameters Δb* (p=0.003) and Δa* (p=0.014). Two weeks post-bleaching, the at-home treatment resulted in significant color improvement compared to in-office treatment for the parameters Δb* (p=0.037) and ΔE00 (p=0.033). No differences were observed in either ΔSGU parameters. Concerning sensitivity, patients treated with in-office bleaching reported more tooth sensitivity than the at-home group only on the first day after bleaching started, without significant differences in the other periods evaluated (p&gt;0.05). Conclusions: At-home and in-office bleaching, preceded by a desensitizing agent, were effective for vital teeth bleaching and 10% carbamide peroxide produced a higher whitening effect than 35% hydrogen peroxide in the short time evaluation. Tooth sensitivity rates were similar for the two techniques tested

Do the clinical practice guidelines for paediatric dentistry meet the quality standards? A meta‐research and quality appraisal using the AGREE II tool

Background: Clinical practice guidelines (CPGs) enhance health care and aid clinicians' decisions. Aim: To evaluate the quality of clinical guidelines in paediatric dentistry using the AGREE II tool. Design: PubMed, EMBASE, Scopus, LIVIVO, Lilacs, international guidelines websites, scientific societies, and gray literature were searched until September 2021. We included paediatric dental clinical guidelines and excluded drafts or guidelines for patients with special needs. Two independent reviewers performed quality assessment using the APPRAISAL OF GUIDELINES FOR RESEARCH & EVALUATION II (AGREE II) instrument. We calculated the mean overall domain scores (95% confidence interval) for each guideline. We used regression analysis to correlate the score of overall assessment and the six domains of AGREE II with guideline characteristics. Results: Forty‐four guidelines were included in this study. Highest mean score was for Domain 4 (Clarity of Presentation; 58%, 95% CI: 50.8–64.9), whereas the lowest was for Domain 5 (Applicability; 16%, 95% CI: 10.8–21.4). The reporting quality was improved in Domains 1–5 with reporting checklists (p < .001), whereas that of Domain 6 was improved by decreasing years since publication (p = .047). Conclusion: Paediatric dental guidelines do not comply with the methodological quality standard, especially in Domain 5 (Applicability). The AGREE reporting checklist should be implemented with a system to evaluate the certainty of evidence for future guidelines