LAUSR

Aim: The aim of this in vitro study was to evaluate the antibacterial activity of gypsum-based biomaterial with different concentrations of chitosan (GP/CT) and to compare with the commercial dental materials, Dycal and glass ionomer cement (GIC) against the Streptococcus mutans. Materials and Methods: GP/CT was prepared with different concentrations of CT to GP of 0%, 10%, 20%, 40%, and 80% (w/w). The antibacterial study was carried out using agar diffusion method on Mueller-Hinton agar (MHA) against S. mutans. Uniform wells were prepared at equidistant points in the base layer of MHA. The wells were filled with the materials immediately after manipulation and preincubated for 2 h and then incubated. The means of inhibition zones were measured at 48 and 72 h. Results: The results revealed that higher means of inhibition zone were observed in a dose-dependent manner with higher concentrations of CT. GP/80%CT showed more effective antibacterial effect than GP/20%CT and GP/10%CT with significant degree and also with GP/40%CT with no significant result (P < 0.05), while GP/0%CT showed no inhibition of bacterial growth. GP/80%CT showed no statistically significant difference with GIC and Dycal on day 3. In addition, no significant bacterial growth inhibition was observed between GP/40%CT and GIC. Conclusion: Gypsum-based biomaterial has potent antibacterial activity against S. mutans when CT added. Higher antibacterial activity of GP/CT biomaterial was observed in a dose-dependent manner with higher concentrations of CT. GP/80%CT exhibits the antibacterial effect similar to that of Dycal and GIC.