Methodological quality of network meta-analysis in dentistry: a meta-research

Abstract This meta-research aimed to provide an overview of the methodological quality and risk of bias of network meta-analyses (NMA) in dentistry. Searches for NMA of randomized clinical trials with clinical outcomes in dentistry were performed in databases up to January 2022. Two reviewers independently screened titles/abstracts, selected full texts, and extracted the data. The adherence to PRISMA-NMA reporting guideline, the AMSTAR-2 methodological quality tool, and the ROBIS risk of bias tool were assessed in the studies. Correlation between the PRISMA-NMA adherence and the AMSTAR-2 and ROBIS results was also investigated. Sixty-two NMA studies were included and presented varied methodological quality. According to AMSTAR-2, half of the NMA presented moderate quality (n = 32; 51.6%). The adherence to PRISMA-NMA also varied. Only 36 studies (58.1%) prospectively registered the protocol. Other issues lacking of reporting were data related were data related to the NMA geometry and the assessment of results consistency, and the evaluation of risk of bias across the studies. ROBIS assessment showed a high risk of bias mainly for domains 1 (study eligibility criteria) and 2 (identification and selection of studies). Correlation coefficients between the PRISMA-NMA adherence and the AMSTAR-2 and ROBIS results showed moderate correlation (rho < 0.6). Overall, NMA studies in dentistry were of moderate quality and at high risk of bias in several domains, especially study selection. Future reviews should be better planned and conducted and have higher compliance with reporting and quality assessment tools.

Adesão ao formato preprint por docentesde odontologia das universidades públicas do Rio Grande do Sul / Adherence to the preprint format by dentistry professors from public universities in Rio Grande do Sul

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 MedArxive 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 dife-rentes 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 resul-tados 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 com-paração 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.

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). Mate-rials 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 platfor-ms, 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 pre-prints (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.

Pulp vitality of primary molars with deep caries treated with ART restorations: 2-year RCT

Abstract: The aim of this study was to compare the pulp vitality of primary teeth with deep caries treated with two restorative techniques. The restoration survival rate was also evaluated as a secondary outcome. Children aged from 4 to 8 years with at least one deep carious lesion in molars were selected at the Ibirapuera University dental clinic. One hundred and eight deciduous molars were allocated into two groups: (1) restoration with calcium hydroxide cement lining followed by filling with high-viscosity glass ionomer cement (CHC+HVGIC) or (2) restoration with HVGIC. Pulp vitality and restoration survival were evaluated at 6, 12, and 24 months. Intent-to-treat analysis was used for pulp vitality, and survival analysis was performed with the Kaplan-Meier method (α=5%). Results: At 24 months, 86 restorations were evaluated, and 91 were evaluated at least once during the study. There was no significant difference between the restorative treatments regarding pulp vitality (CHC +HVGIC=70% and HVGIC=68.5%) (OR=1.091; CI95%=0.481-2.475). However, HVGIC (73%) restorations showed a higher survival rate than CHC+HVGIC (50%) (p=0.021). Thus, it can conclude that deep caries in primary molars should be restored with HVGIC, since the technique results in similar pulp vitality to the CHC +HVGIC, but with a higher restoration survival rate.

Glass fiber post treatment - does it influence resin cement bond strength? / Pinos de fibra de vidro pós tratamento - influencia a resistência de união do cimento resinoso?

Abstract Introduction Glass-fiber posts are used in order to improve the retention of restorations in endodontically treated teeth. Objective To evaluate the bond strength of glass-fiber posts submitted to different surface treatments and cemented to the root canal dentin with self-adhesive resin cement. Material and method Thirty roots of human canines were prepared and divided according to two factors: surface treatments (silane, 35% hydrogen peroxide, or sodium bicarbonate) and root thirds (cervical and middle thirds). The glass-fiber posts were cemented with self-adhesive resin cement (RelyX U200). After 24 h, the specimens were prepared for microtensile bond strength test (hourglass format), fracture pattern and micromorphological assessment by scanning electronic microscopy, in order to measure the cement line. Result The data (MPa and µm) were submitted to two-way ANOVA and Tukey's test (α = 5%). The surface treatments influenced the bond strength of the posts cemented with self-adhesive resin cement (p<0.00). The mean bond strength (standard deviations) differed according to the region of root dentin (p<0.00): the cervical region (Control: 19.16MPa (3.71); Silane: 25.65MPa (4.04); Hydrogen peroxide: 24.43MPa (3.16); Sodium bicarbonate: 37.42MPa (8.27)) showed higher bond strength values than the middle third of the root (Control: 14.66MPa (4.65); Silane: 12.52MPa (5.03); Hydrogen peroxide: 10.64MPa (3.33); Sodium bicarbonate: 10.87MPa (2.49)). Conclusion Treatment of the glass-fiber post surface with chemical and physical agents increased the bond strength of the cement-post-dentin interface in the cervical third and the treatment with Sodium bicarbonate showed better results in bond strength.

Resumo Introdução Pinos de fibra de vidro são utilizados para melhorar a retenção das restaurações em dentes tratados endodonticamente. Objetivo Avaliar a resistência de união de pinos de fibra de vidro submetidos a diferentes tratamentos superficiais e cimentados à dentina radicular com cimento resinoso autoadesivo. Material e método trinta raízes de caninos humanos foram preparadas e divididas de acordo com dois fatores: tratamentos de superfície (silano, peróxido de hidrogênio a 35% ou bicarbonato de sódio) e o terço radicular (cervical e médio). Os pinos de fibra de vidro foram cimentados com cimento resinoso autoadesivo (RelyX U200) e foram divididos de acordo com duas regiões: cervical e terço médio. Após 24 horas, foram preparados para microtração (formato de ampulheta), padrão de fratura e avaliação micromorfológica por microscopia eletrônica de varredura, para medir a linha de cimento. Resultado Os dados (MPa e µm) foram submetidos à ANOVA two-way e teste de Tukey (α = 5%). Os tratamentos de superfície influenciaram a resistência de união dos pinos. A média da resistência de união (desvio padrão) diferiu de acordo com a região da dentina radicular (p <0,00): a região cervical (Controle: 19,16Mpa (3.71); Silano: 25,65MPa (4.04); Peróxido de hidrogênio: 24,43MPa (3.16); Bicarbonato de sódio: 37,42MPa (8.27)) apresentou valores de resistência a raiz (Controle: 14,66MPa (4.65); Silano: 12,52MPa (5.03); peróxido de hidrogênio: 10,64MPa (3.33); bicarbonato de sódio: 10,87MPa (2.49)). Conclusão O tratamento com agentes químicos e físicos aumentou a resistência de união da interface cimento-pino-dentina no terço cervical e o tratamento com bicarbonato de sódio apresentou melhores resultados na resistência de união.

Survival, reasons for failure and clinical characteristics of anterior/posterior composites: 8-year findings

Abstract This retrospective study aimed to compare the annual failure rate (AFR), reasons for failure and factors influencing survival of posterior and anterior composite restorations placed by undergraduate students. Composite restorations placed by undergraduate students were evaluated. The restorations should be in occlusion, with at least one adjacent tooth; and patients should have been present for check-up, with at least 1 annual recall. The investigation was performed in two separate analysis: 1) dental electronic records of 100 patients (n=333 restorations) were selected to assess factors influencing survival; 2) clinical evaluation of 30 patients by examining restorations (n=123) to assess clinical characteristics and failure type distribution. Data were subjected to Kaplan-Meier method, Log-rank test, Cox regression and Fisher's Exact test (p<0.05). After 8-year period, the AFR was 2.62%. There was difference between anterior and posterior restorations (p=0.005), with anterior showing a higher AFR. The patient caries-risk (p<0.001) and the number of surfaces restored (p=0.010) affected restoration survival. The superficial brightness (p=0.029), fracture (p=0.025) and retention (p=0.011) were clinical criteria with differences between anterior and posterior restorations. Income (p<0.001), caries activity (p<0.001), caries risk (p<0.001) and oclusal risk (p<0.001) also influenced on the restorations survival. After 8-year, the AFR of restorations placed by undergraduate students was acceptable and affected by patient risk factors and the position of the tooth in the arch: anterior restorations failed more than posterior.

Resumo Este estudo retrospectivo comparou a taxa de falha anual (TFA), razões para falha e fatores influenciadores da sobrevida de restaurações posteriores e anteriores de resina composta realizadas por estudantes de graduação. As restaurações deveriam estar em oclusão, com pelo menos um dente adjacente, e os pacientes deveriam ter comparecido a pelo menos 1 consulta anual de retorno. A investigação foi realizada em 2 analises separadas: 1) dados odontológicos de prontuário eletrônico de pacientes (n=333 restaurações) foram selecionados para avaliar os fatores influenciadores na sobrevida; 2) avaliação de 30 pacientes por exame clinico das restaurações (n=123) para verificar as características clinicas e a distribuição do tipo de falha. Os dados foram submetidos a Kaplan-Meier método, Log-rank teste, regressão de Cox e Teste Exato de Fisher (p<0,05). Após o período de 8 anos, a TFA foi 2,62%. Houve diferença entre restaurações anteriores e posteriores (p=0,005), sendo que anteriores mostraram maior TFA. Os fatores de risco à carie (p<0,001) e o número de superfícies restauradas (p=0,010) influenciaram a sobrevida de restaurações. Brilho superficial (p=0,029), fratura (p=0,025) e retenção (p=0,011) foram critérios clínicos com diferenças entre restaurações anteriores e posteriores. Renda (p<0,001), atividade de cárie (p<0,001), risco à cárie (p<0,001) e risco oclusal (p<0,001) também influenciaram a sobrevida. Após 8 anos, a TFA das restaurações realizadas por estudantes de graduação foram clinicamente aceitáveis e afetadas pelos fatores de risco associados ao pacientes e a posição do dente na arcada; restaurações anteriores falham mais do que posteriores.

Effect of sodium hypochlorite as dentinal pretreatment on bonding strength of adhesive systems.

Aim: This study aimed to evaluate the effect of sodium hypochlorite (NaOCl) pretreatment on bond strength of adhesive systems to different dentin regions. Materials and Methods: Forty human molars were randomly assigned according to different adhesive systems (Adper Single Bond 2; Clearfil SE Bond; Adper SE Plus; G‑Bond), pretreatments (control and NaOCl ‑ deproteinization) and dentin regions (proximal, superficial occlusal [SO] and deep occlusal [DO]), n = 5. Cylindrical cavities were performed at the proximal and occlusal surfaces of each sample. For deproteinization, 10% NaOCl was applied on conditioned dentin for 60 s before the adhesive systems application. Two occlusal and one proximal slice were obtained from each sample and submitted to the push‑out test. The mode of fracture was analyzed. The data were subjected to three‑way ANOVA and Tukey test (P < 0.05). Results: There was statistically significant difference between the adhesive systems (P < 0.01) and dentin regions (P < 0.01); however, the pretreatment did not significantly affect the bond strength values (P > 0.05). The bond strength values were higher for the proximal surface, followed by SO and later by DO, being influenced by the adhesive system. The two‑step self‑etch adhesive systems presented the highest bond strength results. Conclusion: The deproteinization pretreatment showed similar bonding effectiveness to the conventional adhesive technique. The dentin region plays a rule on the bond strength values.

Effect of Pre-treatment with Chlorhexidine on the Retention of Restorations: A Randomized Controlled Trial

This study aimed to evaluate the effect of chlorhexidine (CHX) application on etched dentin on the 6-month retention of restorations placed on non-carious cervical lesions (NCCLs). A randomized controlled split-mouth and triple blind trial was carried out. Patients (n=42) with at least two non-carious cervical lesions were included. NCCLs were randomly assigned to two groups: control (placebo solution) or test group (2% CHX solution for 60 s after acid etching and before the adhesive application). Class V restorations (n=169) were performed with an etch-and-rinse adhesive system and composite resin by 10 trained operators. A calibrated examiner evaluated the restorations at 1 week (baseline) and at 6 months using the FDI criteria. The primary outcome was retention of the restorations. The analysis of factors associated to failure of restorations was carried out by Fisher's exact test (α=0.05). After 6 months of follow-up, 3.4% (CI 95% 1.3-7.3) of the restorations failed. There was no statistically significant difference between control and CHX (p=0.920). Regarding the cavity variables, deeper (p=0.04), wider (p=0.004) and wedge-shaped (p=0.033) cavities failed more. Both treatments provided acceptable clinical performance of the restorations. The use of CHX as a adjuvant in dentin adhesion did not influence the retention of Class V restorations after 6 months of follow-up.

O objetivo deste estudo foi avaliar o efeito da aplicação de clorexidina (CRX) em dentina condicionada na retenção de restaurações confeccionadas em lesões cervicais não-cariosas (LCNC) após 6 meses. Ensaio clínico randomizado triplo cego do tipo boca dividida foi conduzido. Pacientes (n=42) com no mínimo duas LCNC foram incluídos. LCNC foram randomizadas em dois grupos: controle (solução placebo) ou grupo teste (aplicação de CRX 2% por 60 s após o condicionamento e antes da aplicação do adesivo). Restaurações Classe V (n=169) foram realizadas com adesivo de condicionamento ácido total e resina composta, por 10 operadores treinados. Um examinador calibrado avaliou as restaurações após 1 semana (base) e 6 meses usando os critérios da FDI. O desfecho primário foi retenção das restaurações. A análise dos fatores associados à falha das restaurações foi conduzida com Teste Exato de Fisher (α=0,05). Após 6 meses de acompanhamento, 3,4% (IC 95% 1,3-7,3) das restaurações falharam. Não houve diferença estatística entre os grupos CRX e controle (p=0,920). Com relação às variáveis das cavidades, cavidades mais profundas (p=0,024), largas (p=0,004) e em formato de cunha (p=0,033) falharam mais. Ambos os tratamentos (CRX e controle) proporcionaram performance clínica aceitável das restaurações. O uso de CRX como coadjuvante na adesão à dentina não influenciou a retenção das restaurações Classe V após 6 meses de acompanhamento. .

Influence of Cariogenic Challenge on Bond Strength Stability of Dentin

The aim of this study was to evaluate the effect of cariogenic challenge on the microtensile bond strength values (μTBS) of dentin pre-treated with chlorhexidine digluconate (CHX) or sodium hypochlorite (NaOCl). Thirty-six sound molars were selected and randomly assigned to 3 dentin pre-treatments (distilled water - control, 2% CHX and 10% NaOCl) and 4 aging protocols (24h control, biofilm without cariogenic challenge, biofilm with cariogenic challenge, and 18-month water storage). The same etch-and-rinse adhesive system and composite resin were used for all groups (n=30 beams). For the biofilm groups, dental microcosm biofilms originated from saliva of a healthy donor were grown on the samples with a defined medium enriched with mucin, with or without 10% sucrose, according to the group. After the experimental period, the microtensile test was performed. Data were analyzed with ANOVA followed by Tukey test (p<0.05). The pre-treatment did not influence μTBS for all aging conditions (p=0.188), but the type of aging affected the bond strength (p<0.001). Cariogenic challenge and water storage aging affected the bond stability resulting in a decrease of the μTBS, but the pre-treatments did not influence the μTBS.

O objetivo neste estudo foi avaliar o efeito do desafio cariogênico na resistência de união (RU) da dentina pré-tratada com clorexidina (CRX) ou hipoclorito de sódio (NaOCl). Trinta e seis molares hígidos foram selecionados e randomizados de acordo com 3 pré-tratamentos dentinários (controle, CRX a 2% e NaOCl a 10%) e 4 protocolos de envelhecimento (controle 24h, biofilme sem desafio cariogênico, biofilme com desafio cariogênico, e armazenamento de 18 meses em água). O mesmo sistema adesivo e resina composta foram usados para todos os grupos (n=30). Biofilme dental de microcosmo originado da saliva de doador saudável foi desenvolvido sobre as amostras com meio enriquecido com mucina adicionada ou não com sacarose a 10%, de acordo com o grupo. Após o período experimental, o teste de microtração foi realizado. Os dados de microtração foram analisados com ANOVA a dois fatores e teste de Tukey (p<0,05). O pré-tratamento não influenciou os valores de RU para todos os protocolos de envelhecimento (p=0,188), porém o tipo de envelhecimento influenciou os valores de RU (p<0,001). O desafio cariogênico e o armazenamento em água afetaram a estabilidade adesiva resultando na diminuição dos valores de RU e o pré-tratamento não influenciou os valores de RU.