A rescent study by Zhou, et al investigated the potential of adverse effects of chlorhexidine application in a 2-step self-etching adhesive on the immediate resin-dentin bond strength. By adding different amounts of chlorhexidine digluconate directly to Clearfil SE Bond primer [Kuraray Dental], 4 different concentrations of chlorhexidine were assessed: 0.05 wt%, 0.1 wt%, 0.5 wt%, and 1.0 wt%. Using extracted third molars, 16 teeth were randomly divided into 4 groups, corresponding to one of the 4 chlorhexidine concentrations. After sectioning each of the 16 teeth into halves, one half was customarily bonded with Clearfil SE Bond without chlorhexidine, and the other half was bonded with Clearfil SE Bond containing different concentrations of chlorhexidine. Immediately following this, microtensile bond strengths were tested, and the modes of fractures were examined under a stereomicroscope. The study found no significant difference of immediate resin-dentin bond strength between the control groups and any of the experimental groups containing chlorhexidine (P > .05). The study concludes that the addition of chlorhexidine to a 2-step self-etching adhesive primer (Clearfil SE Bond primer) has no adverse effect on the immediate resin-dentin bond strength when the chlorhexidine concentration in the primer is lower than or equal to 1.0 wt%.
(Source: Journal of Adhesive Dentistry, 2010, Volume 12, Number 1, pages 27 to 31.)