Métodos de envelhecimento da interface adesiva para testes de adesão à dentina

Abstract

The aim of this study was to evaluate the effect of degradation of resin-dentin interface, measured by the decrease of the bond strength (BS) after different available methods for simulation of accelerated aging. The work was divided into two studies: (1) a systematic review and meta-analysis of the literature; and (2) an in vitro experiment. The first study was described according to PRISMA to investigate whether the different accelerated aging methods and protocols are effective in reducing bond strength to dentin using direct composite resin. It was identified that the thermal cycling had a significant effect in most of the protocols used for the aging of the interface. Mechanical and thermomechanical cycling, pulpal pressure, NaOCl storage and thermal cycling + static storage were able to promote the decrease of BS. Enzyme storage was only able to decrease the BS in periods of at least 3 months; and the pH cycling and cariogenic challenge protocols evaluated were not able to promote the decrease of the BS. The second study tested 5 of the available methodologies in the laboratory (thermal cycling, mechanical cycling, mechanical cycling with Rub & Roll, cariogenic challenge and 5 weeks of storage in water) and evaluated microtensile bond strength. Two types of adhesive were used for this experiment (etch-and-rinse and self-etch) and the control group remained in water (37 C) for 24 hours. It was observed that 14 days of cariogenic challenge were able to reduce the BS of the etch-and-rinse adhesive system and the mechanical cycling of the self-etch. With this thesis we can conclude that many methods of accelerated aging can be effective in the degradation of interface, however, many parameters should be considered as aging time, storage conditions and material used.