Pre-treating dentin with chlorhexadine and CPP-ACP: self-etching and universal adhesive systems.

The aim of the present study was to compare the effect of pre-treating dentin with chlorhexidine, at concentrations of 0.2% and 2%, and remineralizing paste containing CPP-ACP (MI Paste - GC) on the bond strength of adhesive systems. In total, 80 slides of dentin were used. These slides were 2 mm thick and were obtained from bovine incisors. Standard cavities were created using diamond bur number 3131. In the control groups, a Scotchbond Universal Adhesive (SUA) self-etching adhesive system of 3M ESPE and a Clearfil SE Bond (CSE) adhesive system of Kuraray were applied, following the manufacturer's instructions. In the other groups, dentin was pretreated with chlorhexidine (0.2% and 2%) for 1 min and with MI Paste for 3 min. The cavities were restored with Z350 XT resin (3M ESPE). After 24 h of storage, the push-out test was applied at a speed of 0.5 mm/min. The different dentin pretreatment techniques did not affect the intra-adhesive bond strength. There was a difference between treatment with MI Paste and chlorhexidine 0.2% in favor of the SUA, with values of 15.22 and 20.25 Mpa, respectively. The different pretreatment methods did not alter the immediate bond strength to dentin. Differences were only recorded when comparing the adhesives.