Gallium-doped mesoporous bioactive glass nanoparticles for antibacterial and immunomodulatory effects in vital pulp therapy

Vital pulp therapy (VPT) is crucial for the self-repair and long-term retention of teeth with pulpitis. Here, we aimed to develop gallium-doped mesoporous bioactive glass nanoparticles (Ga-MBGNs) as a multifunctional pulp capping material for VPT. Ga-MBGNs were synthesized and systematically characterized, followed by evaluation of their antibacterial, immunomodulatory, and dentinogenic properties using in vitro and in vivo models. In vitro, Ga-MBGNs effectively inhibited endodontic pathogens and promoted odontoblastic differentiation of human dental pulp cells. Mechanistically, they attenuated inflammation by reducing reactive oxygen species, activating the NRF2-HO-1 pathway, and suppressing NF-κB signaling. In a mouse pulp capping model, Ga-MBGNs significantly induced reparative dentin formation, maintained pulp vitality, and reduced inflammation. In conclusion, Ga-MBGNs represent a promising multifunctional pulp capping material with antibacterial, immunomodulatory, and dentinogenic properties, providing a potential strategy for VPT. STATEMENT OF SIGNIFICANCE: Pulpitis remains difficult to treat because current biomaterials cannot simultaneously control infection, regulate inflammation, and induce true tissue repair. In this work, we developed gallium-doped mesoporous bioactive glass nanoparticles (Ga-MBGNs) that directly link material structure to biological function. Their mesoporous architecture enables sustained Ga³⁺ release, which in turn suppresses bacterial growth, reduces oxidative stress, and modulates immune activation through the NRF2/HO-1/NF-κB pathway. This controlled ion delivery also promotes odontogenic differentiation and dentin matrix formation, ultimately preserving pulp vitality in vivo. By integrating antimicrobial, immunoregulatory, and regenerative capabilities within a single nano-engineered platform, this study introduces a structurally defined and functionally active biomaterial with clear potential to advance vital pulp therapy and regenerative dental medicine.