Bactericidal activity and cytotoxicity of antibacterial monomer MDPB

The aim of this study was to investigate bactericidal characteristics and c ytotoxicity of the newly developed antibacterial monomer 12-methacryloyloxy dodecylpyridinium bromide (MDPB). To evaluate the bactericidal activity of MDPB against oral streptococci, the minimum bactericidal concentration (MBC ) for seven species and time-kill kinetics against Streptococcus mutans wer e determined. The cytotoxic effects of MDPB on human pulpal cells were asse ssed by [H-3]-thymidine uptake after contact with MDPB solutions at various concentrations. MDPB showed strong bactericidal activity against seven str eptococci, the MBC value ranging from 31.1 to 62.5 mu g ml(-1). Time-kill d etermination indicated a rapid killing effect of MDPB at 250 mu g ml(-1) or over, and all cells were billed within 1 min by MDPB at 500 mu g ml(-1) or over. No cytotoxic effect was observed on contact with MDPB at concentrati ons of 10 mu g ml(-1) or less, and the toxicity of MDPB was considered to b e similar to those of other monomers used for dental materials. These resul ts suggest that MDPB can be effectively incorporated in dental resin-based materials to provide bactericidal activity against oral bacteria. (C) 1999 Elsevier Science Ltd. All rights reserved.