Bioactive Glass-Containing Resin Composites: Enamel Protection, Mineralization Potential, and Translational Challenges

Bioactive glass (BAG)-containing resin composites have attracted interest as restorative materials that may provide functions beyond conventional mechanical restoration. By releasing biologically relevant ions and modifying the local chemical environment, these materials may reduce mineral loss and promote mineral deposition at the tooth–restoration interface. Laboratory studies have investigated their effects on enamel and dentin, as well as their mechanical properties, antibacterial potential, and suitability for restorative applications. However, the reported outcomes vary according to glass composition, particle size, filler concentration, resin formulation, and experimental conditions. Increasing the proportion of bioactive glass may enhance ion release and mineral-forming activity, but it can also affect polymerization, strength, wear resistance, and long-term stability. Moreover, most available evidence is derived from laboratory experiments, and the extent to which these findings translate into clinically meaningful benefits remains uncertain. This narrative review discusses the proposed mechanisms of BAG activity, current evidence for protection against demineralization, material-design considerations, and the principal barriers to clinical translation. Further research should prioritize standardized testing, long-term evaluation under clinically relevant conditions, and well-designed clinical studies before the routine use of these materials can be recommended.