A dental filling composite resin restorative with improved antibacterial function and hardness

A novel antimicrobial dental composite resin has been developed and evaluated. Alumina filler particles were covalently coated with an antibacterial resin and blended into a composite resin formulation. Surface hardness and bacterial viability were used to evaluate the modified composite resin. Results showed that almost all the modified composite resins exhibited higher antibacterial activity along with improved surface hardness, as compared to unmodified one. Effects of antibacterial moiety content on the modified fillers, modified alumina particle size and loading, and total filler content were investigated. It was found that increasing antibacterial moiety content, particle size and loading of the modified filler, and total filler content generally increased surface hardness. Increasing antibacterial moiety, filler loading and total filler content increased antibacterial activity. On the other hand, increasing particle size showed a negative impact on antibacterial activity. The leaching tests indicate that the modified experimental composite resin showed no leachable antibacterial component to bacteria and 3T3 mouse fibroblasts.