Development of a Novel Cavity Disinfectant Containing Antibacterial Monomer MDPB

Objectives: To develop a novel cavity disinfectant for indirect/direct restorations or core build-up, an experimental disinfecting solution containing an antibacterial monomer MDPB (12-methacryloyloxydodecylpyridinium bromide) was prepared. In this study, the antibacterial effects and influences on bonding abilities of resin-based luting cements of the experimental disinfectant were evaluated.
Methods: The antibacterial activity of unpolymerized MDPB against seven oral bacteria were compared with those of chlorhexidine digluconate (CHX) or cetylpyridinium chloride (CPC) by determining the minimal inhibitory/bactericidal concentrations (MIC/MBC).
The heavily- and lightly-infected dentin models were fabricated by incubating dentin blocks in Streptococcus mutans NCTC10449 suspension at different concentrations, and the number of residual bacteria after application of the experimental solution containing 5% MDPB (ACC) and the commercial disinfectant containing 2% CHX (Consepsis, Ultradent, CPS) were compared.
The shear bond strength of Panavia F2.0 (Kuraray) and a self-adhesive resin cement, SA cement (Kuraray) to bovine enamel and dentin were measured with application of ACC and CPS.
Results: Unpolymerized MDPB demonstrated strong antibacterial activities against seven anaerobes although its MIC/MBC values were greater than those of CHX or CPC. ACC demonstrated significantly greater bactericidal activity than CPS for both infected models (Tukey’s test, p < 0.05), achieving complete killing of bacteria in dentinal tubules in the lightly-infected model.
While application of CPS significantly reduced the bond strength to dentin of SA cement (p < 0.05), no differences in bond strength between the ACC-treated group and the control without application of disinfectants were observed for both cements.
Conclusions: The experimental cavity disinfecting solution containing MDPB was found to be more useful than the commercially available CHX disinfectant, showing greater effectiveness in eradicating bacteria in infected dentin and no adverse influences on bonding abilities of resin luting cements.