Nadia Alaee, Soodabeh Kimyai, Solmaz Maleki Dizaj, Simin Sharifi
Introduction: Glass Ionomer Cements (GICs), commonly used in restorative dentistry, demonstrate favorable biocompatibility and chemical bonding to tooth structures. However, their antibacterial properties are often inadequate, potentially leading to secondary caries due to biofilm formation on the material's surface. Incorporating Titanium Dioxide (TiO₂) nanoparticles into GICs has emerged as an effective strategy to enhance their antimicrobial properties. Methods: This study investigated the solubility and water sorption of a self-cured restorative dental GIC modified with TiO₂ nanoparticles at concentrations of 0%, 0.5%, 1%, and 3%. The antimicrobial and antibiofilm effects of the TiO₂-modified GIC were then evaluated against Streptococcus mutans (S. mutans) using a series of in vitro assays, including disk diffusion, Minimum Inhibitory Concentration (MIC), and Minimum Biofilm Inhibitory Concentration (MBIC). Results: A statistically significant difference was observed in the inhibition zones among the groups (P = 0.001), with the 3% TiO₂ group showing significantly greater antimicrobial activity compared to the 1% (P = 0.02) and 0.5% (P = 0.001) groups. TiO₂ addition also significantly enhanced resistance to biofilm formation (P = 0.0001), with the 3% group again demonstrating superior results over 1% (P = 0.0001) and 0.5% (P = 0.0001). Regarding solubility, there was a significant difference between groups (P = 0.001), and the 3% group exhibited the lowest solubility (P = 0.0001). No statistically significant difference was found in water sorption among the groups (P = 0.1). Conclusion: This novel approach shows promise for reducing the risk of secondary caries in clinical applications.