Synergistic Antibacterial Remineralization: A Bioprocessing-Inspired Single-Step Nanoparticle-Induced Liquid...

Area of Science:

• Biomaterials Science
• Nanotechnology
• Dental Regenerative Medicine

Background:

• Bacterial invasion impairs dentin's natural repair, driving caries progression.
• Developing strategies for simultaneous dentin restoration and oral biofilm control is challenging.

Purpose of the Study:

• To present a single-step biomimetic approach for synergistic dentin regeneration and antibacterial therapy.
• To utilize carboxyl-functionalized gold nanoparticles (AuNPs-COOH) as a noncollagenous protein analogue.
• To create a nanoparticle-induced liquid precursor (NILP) for enhanced dentin repair and caries prevention.

Main Methods:

• AuNPs-COOH were used to stabilize amorphous calcium phosphate precursors, inducing intrafibrillar mineralization for dentin remineralization.
• The remineralized dentin's mechanical properties (elastic modulus and hardness) were evaluated.
• Dual antibacterial functionalities (photothermal and photodynamic) were activated by near-infrared (NIR) light.
• In vitro and in vivo antibacterial efficacy against Streptococcus mutans biofilms was assessed.
• Biocompatibility with dental pulp stem cells and systemic toxicity were evaluated in animal models.

Main Results:

• The AuNPs-COOH-mediated NILP system restored dentin's hierarchical architecture and mechanical properties, closely matching sound dentin.
• Remineralized dentin exhibited dual NIR-activated antibacterial functionalities, significantly inhibiting Streptococcus mutans biofilm formation in vitro (10-20% of control).
• Robust in vivo antibacterial efficacy, excellent biocompatibility with dental pulp stem cells, and minimal systemic toxicity were observed.

Conclusions:

• The AuNPs-COOH-mediated NILP system offers a promising synergistic strategy for functional dentin regeneration.
• This approach effectively combats oral biofilms and prevents caries progression.
• The biomimetic nanoparticle system represents a significant advancement in dental regenerative medicine and caries prevention.