Work

Engineering a Self‐Defensive Restoration‐Tooth Interface via Bioactive nMgO/E‐POSS Bulk‐Fill Resin Composites for Enhanced Dental Restorations

Year: 2025

Type: article

Abstract: ABSTRACT Light‐curing resin composites (RCs) are widely used for tooth defect restoration. However, challenges such as high polymerization shrinkage and lack of anti‐cariogenic activities compromise interfacial integrity and significantly increase restoration failure risks. To address these limitations, we developed a bioactive multifunctional bulk‐fill RC by integrating sol‐gel‐synthesized monodisperse nano‐MgO (nMgO), Stöber‐derived monodisperse submicron spherical silica (sSiO 2 ), and dendritic epoxy‐cyclohexyl functionalized polyhedral oligomeric silsesquioxane (E‐POSS). RCs achieved a larger depth of cure (DOC > 4 mm) and higher degree of conversion (>80%), enabling reliable clinical handling. nMgO/E‐POSS may synergistically enhance the restoration‐tooth interface through: (1) low shrinkage and reduced shrinkage stress via E‐POSS‐mediated cationic ring‐opening polymerization and rigid structure, effectively minimizing interfacial gaps and microleakage after 10,000 thermal cycles; (2) potent antibacterial activity against Streptococcus mutans through nMgO‐mediated mechanisms including direct contact inhibition, Mg 2 ⁺/ROS generation, and alkaline microenvironment creation; and (3) E‐POSS‐guided biomimetic remineralization of demineralized dentin through Ca‐P deposition and the stabilizing effect of Mg 2 ⁺ on amorphous calcium phosphate. Our novel RCs also maintain clinically satisfactory mechanical properties, hydrolytic/thermal stability, and excellent biosafety. By synergizing self‐defensive antibacterial‐remineralization capabilities with low‐shrinkage‐enhanced interfacial adaptation, this multifunctional composite provides a promising strategy for restoring large dental defects while preventing secondary caries and extending restoration longevity.

Source: Advanced Healthcare Materials

DOI: 10.1002/adhm.202502057