Adesivo autocondicionante contendo vidro bioativo 45s5: resistência de união e nanoinfiltração em dentina afetada por Carie.

Abstract

Objective: The objective of this in vitro study was to evaluate the performance of self-etching adhesive systems containing 45S5 bioactive particles applied to demineralized dentin by caries. Materials and methods: Forty-two healthy human molars were used, half of which underwent artificial caries induction, followed by selective removal of carious tissue. Three experimental self-etching adhesive systems were developed: Experimental control adhesive (without glass - 0%), adhesive containing 5% (by weight) of 45S5 glass (45S5 5%) and adhesive containing 20% (by weight) of 45S5 glass (45S5 20 %). The adhesives were on the dentin surface and the teeth were restored and cut. The proof tests were taken to bodies of a universal testing machine (Instron 3342) for the test of bond strength in the period of 24 hours. The interface of the fractured specimens was observed in a stereomicroscope to obtain the fracture mode. For the nanoinfiltration test, specimens were infiltrated with silver nitrate and an interface was analyzed using a Scanning Electron Microscope (SEM). The data were discovered using the ANOVA test (two-way), post-Holm-Sidak test (α = 0.05). Results: There was a reduction in bond strength (p = 0.03) and an increase in nanoinfiltration (p = 0.04) of the control adhesive in carious dentin compared to a healthy dentin. The bioactive adhesives in the two grades did not show significant statistical differences in the evaluation between the healthy and decayed dentin in both tests performed (p> 0.05). The adhesive with 20% 45S5 had a lower bond strength in the healthy group compared to the control adhesive (p = 0.003) and 5% (p = 0.02). Conclusion: An incorporation of 45S5 bioactive glass particles in experimental self-etching adhesive systems at a concentration of 5% (wt) does not impair the bond strength and is capable of maintaining as stable nano-infiltration rates of the adhesive interface in carious dentin after 24 hours.