Is Conventional Resin Cement Adhesive Performance to Dentin Better Than Self-adhesive? A Systematic Review and Meta-Analysis of Laboratory Studies.

CLINICAL RELEVANCE: Conventional multistep resin cements presented higher adhesive performance to dentin than simplified self-adhesive cements, which is an important criterion for indirect restoration prognosis. SUMMARY: This study aimed to conduct a systematic review of the literature on laboratory studies assessing bonding performance to dentin of conventional and self-adhesive resin cements, in cementing indirect restorations. This review was reported according to the PRISMA Statement. Of a total of 518 studies, 36 were screened full text and reviewed according to exclusion criteria. Nineteen papers were included in the systematic review and meta-analyses, according to the following inclusion criteria: studies that evaluated the bond strength to dentin of indirect restorations cemented with dual conventional or self-adhesive resin cements and those that presented bond strength data in MPa as an outcome. Statistical analyses were conducted using Rev-Man 5.1. Comparisons were performed with random effects models at 5% significance level. A global analysis comparing conventional and self-adhesive cements and three subgroup analyses comparing immediate and long-term results were performed. Global analysis showed a difference between groups, with conventional resin cements presenting higher bond strength results than self-adhesive resin cements, in immediate and long-term time periods (both p=0.03). Immediate and longterm bond strength results were different for self-adhesive cements, favoring immediate bond strength (p=0.03), but immediate and long-term bond strength results for conventional resin cements were not different (p=0.06). Medium or high risk of bias was found in all studies. Conventional multistep resin cements showed superior overall adhesive performance compared with simplified self-adhesive resin cements when used to cement indirect restorations to dentin.

Degradation of Multimode Adhesive System Bond Strength to Artificial Caries-Affected Dentin Due to Water Storage.

The purpose of this study was to evaluate the influence of water storage on bond strength of multimode adhesive systems to artificially induced caries-affected dentin. One hundred twelve sound bovine incisors were randomly assigned to 16 groups (n=7) according to the dentin condition (sound; SND, artificially induced caries-affected dentin; CAD, cariogenic challenge by pH cycling for 14 days); the adhesive system (SU, Scotchbond Universal Adhesive; AB, All-Bond Universal; PB, Prime & Bond Elect; SB, Adper Single Bond 2; and CS, Clearfil SE Bond), and the etching strategy (etch-and-rinse and self-etch). All adhesive systems were applied under manufacturer's instructions to flat dentin surfaces, and a composite block was built up on each dentin surface. After 24 hours of water storage, the specimens were sectioned into stick-shaped specimens (0.8 mm2) and submitted to a microtensile test immediately (24 hours) or after six months of water storage. Bond strength data (MPa) were analyzed using three-way repeated-measures analysis of variance and post hoc Tukey test (α=5%), considering each substrate separately (SND and CAD). The etching strategy did not influence the bond strength of multimode adhesives, irrespective of the dentin condition. Water storage only reduced significantly the bond strength to CAD. The degradation of bond strength due to water storage was more pronounced in CAD, regardless of the etching strategy.

Bovine tooth is a substitute for human tooth on bond strength studies: A systematic review and meta-analysis of in vitro studies.

OBJECTIVES: This study aimed to systematically review the literature to compare the bond strength values achieved from human and bovine teeth of in vitro studies. DATA AND SOURCE: The PubMed/MEDLINE, ISI Web of Science and Scopus electronic databases were searched to select laboratorial studies that evaluated adhesive systems bond strength to human and bovine teeth. No publication year or language restriction was considered. STUDY SELECTION: From 1,285 potentially eligible studies, 15 were selected for full-text analysis, 11 were included in the systematic review and 9 in the meta-analysis. Two authors independently selected the studies, extracted the data and assessed the risk of bias. Mean differences were obtained by comparing bond strength values between human and bovine teeth (overall analysis), and considering enamel and dentin separately (subgroups analysis). Statistical analysis was performed using RevMan5.1, with random effects model, at a significance level of p=0.05. RESULTS: No significant difference was found between human and bovine teeth (p=0.35), either for enamel (p=0.07) or for dentin (p=0.93) substrates. Low to moderate heterogeneity was found on the meta-analysis. All included studies in the systematic review scored between medium and high risk of bias. CONCLUSIONS: Bovine teeth can be a reliable substitute for human ones on bond strength studies of adhesive systems to both enamel and dentin substrates.