Antibacterial surface properties of various fluoride-releasing restorative materials in vitro

Purpose: The aim of this study was to investigate the antibacterial surface properties of high-viscosity glass ionomers (Fuji IX GP, Ketac Molar), a resin-modified nano-ionomer (Ketac N100), resin-modified glass ionomers (Fuji II LC, Vitremer), a compomer (Compoglass F) and a resin-based composite (Filtek Z250). Methods: ISO-standardized specimens 6 mm in diameter were prepared for each restorative material. The antibacterial properties of the materials were tested in an agar diffusion assay using Streptococcus mutans (ATCC 25175) for 24 and 48 hours. An inhibition zone greater than 6 mm was defined as diffuse inhibition, whereas zones ≤6 mm were described as contact inhibition. Results: All tested materials exhibited a contact antibacterial effect against S. mutans. Vitremer showed the most remarkable antibacterial diffuse inhibition. Conclusions: These materials might cause antibacterial effects against S. mutans when placed on cavity surfaces in both enamel and dentine, thereby preventing secondary caries formation.