The improvement of biocompatibility of adhesives: The effects of resveratrol on biocompatibility and dentin micro-tensile bond strengths of self-etch adhesives

Objective: The aim of this in vitro study is to evaluate the effects of resveratrol (RES) addition on the cytotoxicity and microtensile bond strength (μTBS) of different adhesives. Materials and methods: Five self-etching adhesives (G-aenial Bond-GC, Optibond All in One-Kerr, Gluma Self Etch-Kulzer, Clearfil S3 Bond-Kuraray, and Nova Compo-B Plus-Imicryl) were tested. They were applied to L-929 cell culture by the extract method. In the test groups, 0.5 μM RES (Sigma-Aldrich) was added into the medium. Cell viability was assessed by MTT assay after 24 h. Human extracted third molars were used for μTBS test (n = 7). The adhesives with or without 0.5 μM RES addition were applied on dentin surfaces. A composite build-up was constructed. Then, the specimens were sectioned into multiple beams with the non-trimming version of the microtensile test and subjected to microtensile forces. Statistical analysis was performed using ANOVA and post hoc Tukey test (p ˂ 0.05). Results: The extracts of all adhesives decreased the cell viability. However, RES addition increased the cell viability in all groups (p ˂ 0.05). RES addition did not cause any decrease in μTBS values of the adhesives compared to baseline. Optibond All in One showed the highest μTBS after RES addition. It was followed by Clerafil S3 Bond and Nova Compo-B Plus. No difference was determined between the Optibond All in One and Clearfil S3 Bond. There was difference between Optibond All in One and Nova Compo-B Plus (p ˂ 0.05). Conclusion: RES addition may improve the biocompatibility without causing negative influence on μTBS of the adhesives. Clinical relevance: RES addition has clinical applicable potential to overcome the adverse biocompatibility of adhesives.