Ph-Responsive Mesoporous Silica-Reinforced Composite Resin With Remineralization Capability

The enhancement of mechanical properties in composite resins and dentin remineralization can effectively prolong the service life of dental restorations. This study designed a pH-responsive dental composite resin, of which the filling materials is Pchi/ACP@A-MSNs. Mesoporous silica (A-MSNs) and Pchi/ACP were synthesized, and composite resins were divided into five groups based on filler composition: Group A (45% A-MSNs + 15% Pchi/ACP + 40% resin matrix), Group B (22.5% A-MSNs + 37.5% Pchi/ACP@A-MSNs + 40% resin matrix), Group C (45% non-porous silica + 15% Pchi/ACP + 40% resin matrix), Group D (15% Pchi/ACP + 85% resin matrix), and Group E (100% resin matrix). The degree of double bond conversion (DC) was measured for all groups. Mechanical properties were evaluated. Dentin remineralization was observed via scanning electron microscopy (SEM). Calcium ion release was assessed in different pH environments over 1, 4, 7, 14, 21, and 28 days. Cell viability was determined using the CCK-8 assay. The composite resin containing 45% A-MSNs and 15% Pchi/ACP exhibited the highest mechanical strength, while the resin with only 15% Pchi/ACP demonstrated the most significant dentin remineralization effect. The composite resin with 22.5% A-MSNs and 37.5% Pchi/ACP@A-MSNs showed balanced mechanical performance and Ca²⁺ release, particularly in acidic conditions, where a pronounced increase in Ca²⁺ concentration was observed. The pH-responsive Pchi/ACP@A-MSNs system offers potential for clinical applications in minimally invasive and bioactive restorative dentistry.