pH-Responsive mesoporous silica nanoparticle-reinforced composite resin with remineralization capability

• Published in: BMC oral health Vol. 25; no. 1; pp. 1234 - 16
• Main Authors: Ge, Yongcheng, Zhao, Ting, Liu, Yuguang, Fan, Sizheng, Liu, Pengyuan, Zhao, Chengji, Liu, Xiaoqiu
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 23.07.2025; BioMed Central; BMC
• Subjects: Acids; Biocompatibility; Calcium ion release; Calcium phosphate; Calcium phosphates; Calcium Phosphates - chemistry; Caustic soda; Cell Survival - drug effects; Cell viability; Chitosan; Chitosan - chemistry; Cholecystokinin; Composite materials; Composite Resins - chemistry; Cytotoxicity; Dental caries; Dental cement; Dental composite; Dental restorative materials; Dentin; Elastic Modulus; Ethanol; Ethylenediaminetetraacetic acid; Flexural Strength; Hardness; Humans; Hydrogen-Ion Concentration; Interfacial bonding; Materials Testing; Mechanical properties; Mesoporous silica nanoparticle; Mineralization; Nanoparticles; Nanoparticles - chemistry; NMR; Nuclear magnetic resonance; pH effects; Polymerization; Porosity; Remineralization; Resins; Silica; Silicon Dioxide - chemistry; Tooth Remineralization - methods; Vacuum distillation; China; California; United States > US; Shanghai China; Dentin; Mesoporous silica nanoparticle; Calcium ion release; Dental composite; Remineralization
• DOI: 10.1186/s12903-025-06471-8
• ISSN: 1472-6831

Enhancing the mechanical properties of composite resins and promoting dentin remineralization are effective strategies for extending the longevity of restorations. In this study, we developed a pH-responsive composite resin reinforced with phosphorylated chitosan (Pchi)/amorphous calcium phosphate (ACP) and amino-functionalized mesoporous silica nanoparticles (MSNs) (Pchi/ACP@A-MSN complexes). MSNs and Pchi/ACP were synthesized, and the resulting composite resins were classified into five groups based on the filler compositions: Group A (45wt.% A-MSNs + 15wt.% Pchi/ACP + 40wt.% resin matrix), Group B (22.5wt.% A-MSNs + 37.5wt.% Pchi/ACP@A-MSNs + 40wt.% resin matrix), Group C (45wt.% nonporous silica + 15wt.% Pchi/ACP + 40wt.% resin matrix), Group D (15wt.% Pchi/ACP + 85wt.% resin matrix), and Group E (100wt.% resin matrix). The degree of double-bond conversion and mechanical properties (Flexural modulus, flexural strength, and Vickers hardness) of each group were measured. The remineralization performance and calcium ion (Ca²⁺) release performance were observed. Cell viability was evaluated by CCK-8 assay. Group A exhibited the highest mechanical performance, with flexural strength of 115 ± 9.68 MPa, flexural modulus of 5.99 ± 0.44 GPa, and Vickers hardness of 31.73 ± 2.39 HV. All groups achieved double-bond conversion rates > 50% after 60 s of light curing (P > 0.05). At pH 4.0, Group B exhibited the highest Ca²⁺ release (276 µg/mL), while Group D had the highest release at pH 7.4 (128 µg/mL). SEM and EDS analyses indicated that Group D achieved the most substantial dentin remineralization, followed by Groups C and A. All groups maintained cell viability above 75% throughout the 7-day assay, with no significant cytotoxicity observed. A composite formulation containing 45 wt% A-MSNs and 15 wt% Pchi/ACP (Group A) significantly enhanced mechanical strength. The 15 wt% Pchi/ACP formulation (Group D) demonstrated the greatest remineralization effect. Group B, combining A-MSNs and Pchi/ACP@A-MSNs, provided pH-responsive Ca²⁺ release with a favorable balance of mechanical performance and remineralization potential. All formulations met the biocompatibility requirements for dental applications.