A Unifying Dental Gel for Enamel-Remineralization, and Whitening Effects

This study reports a multifunctional dental gel of calcium peroxide-amorphous calcium carbonate phosphate (CaO₂-ACCP), capable of synergistically repairing damaged dentin, tooth-whitening, and exerting antibacterial activity. The CaO₂ nanoparticles react with water in saliva, releasing Ca²⁺, OH^-, and reactive oxygen species (ROS). The thus-generated alkaline environment and the released Ca²⁺ ions promote the conversion of the ACCP gel into hydroxyapatite (HAP), which is critical for remineralizing damaged dentin and restoring its microhardness (from 0.1 GPa for acid-etched to 2.0 GPa for remineralized). On the other hand, the gel provides an ultralarge surface for concurrent adsorption of ROS and pigment molecules, enabling efficient stain removal and rapid tooth whitening within 12 h. Simultaneously, the gel effectively suppresses pathogenic bacteria growth (almost 100% sterilized within 24 h) and prevents caries. Through the mechanisms of "ROS confinement buffer" and "Ca²⁺-driven positive feedback synergy," an effect of "1+1>2" is achieved. This study demonstrates synergistic intervention across the disease-aesthetic spectrum, promising a gentle and effective solution for comprehensive oral healthcare.