INFLUENCE OF INCORPORATION OF ANTIBACTERIAL MONOMER ON CURING BEHAVIOR OF A DENTAL COMPOSITE

A newly developed monomer, methacryloyloxydodecylpyridinium bromide (M DPB), has an antibacterial activity against oral streptococci, and thi s monomer can be active even after being immobilized as one component of a cured composite. The purpose of this study was to investigate the influence of incorporation of MDPB on the curing behavior of Bis-GMA- based composites. Depth of cure, degree of cure, light-attenuating eff ect, and surface hardness of composites incorporating 0.4 or 0.5% MDPB were measured and compared with those of a control material without M DPB. Depth of cure of composites with MDPB, measured by means of a pen etrometer, was greater than for the control (p < 0.05). Differential t hermal analysis showed that composites with MDPB had a significantly g reater degree of cure than the control (p < 0.05). The light-attenuati ng effect of MDPB composites was less than for the control (p < 0.05). No significant. difference between experimental. and control was obta ined with respect to Vickers hardness after both one day's and seven d ays' storage in water. These results indicate that the incorporation o f small quantities of MDPB into Bis-GMA-based composites did not adver sely affect the cure performance. On the contrary, a significant, thou gh small, improvement was observed.