ABSTRACT
OBJECTIVES: The aim of this study is evaluating the antibacterial activity of resin composites containing ZnO nanoparticles against Streptococcus mutans and examining their physical and mechanical properties. METHODS: The properties of flowable resin composites containing 0-5wt.% nano-ZnO are investigated using different tests: RESULTS: Although the agar diffusion test reveals no significant difference between the groups, the direct contact test demonstrates that by increasing the nanoparticle content, the bacterial growth is significantly diminished (p<0.05). In the aging test, however, the antibacterial properties reduce significantly (p<0.05). The flexural strength and compressive modulus remains unchanged by incorporation of nanoparticles (p>0.05) while the compressive strength and flexural modulus significantly increase (p<0.05). The ZnO containing resins show significantly lower depth of cure (p<0.05), and higher bond strength (p<0.05). There is no significant difference between the degrees of conversion, measured by FTIR technique, of the groups (p>0.05). SIGNIFICANCE: Production of a dental resin composite with antibacterial activity without significant sacrificing effect on the mechanical properties is desirable in dental material science.