The effect of magnesium oxide nanoparticles on the antibacterial and antibiofilm properties of glass-ionomer cement

OBJECTIVES: This study examined the antibacterial and antibiofilm properties of conventional glass-ionomer cement (GIC) modified by the addition of magnesium oxide (MgO) nanoparticles. MATERIALS AND METHODS: MgO nanoparticles were characterised by XRD, FTIR, and SEM analysis and tested for its activity against Streptococcus mutans and Streptococcus sobrinus. MgO nanoparticles were incorporated into GIC powder (Ketac Molar Easymix) at different concentrations and the antibacterial and antibiofilm activity was evaluated using agar disk diffusion and biofilm-CFU counting assays. ANOVA and Tukey's post hoc tests were used for the analysis, and the level of significance was set at p < 0.05. RESULTS: MgO nanoparticles showed antibacterial activity against both microorganisms (MIC = 500 μg/ml and MBC = 1000 μg/ml). A significant difference in the zones of inhibition was detected (p < 0.005). The effect was evident in the 2.5% MgO nanoparticle modified GIC while the CFU counting biofilm assay showed the effect of the added nanoparticles from 1% with a significant difference between the tested material groups (p < 0.005). CONCLUSIONS: The MgO nanoparticle modified GIC showed effective antibacterial and antibiofilm activity against two cariogenic microorganisms and could be considered for further development as a biocompatible antibacterial dental restorative cement.