Integrated two-phase free radical hydrogel: Safe, ultra-fast tooth whitening and antibacterial activity

The growing demand for brilliant smile and tooth whitening has led to the increasing significance of tooth whitening methods. However, the development of tooth whitening materials with high efficiency and safety has been considered to be an urgent challenge. Here, we report a novel tooth whitening strategy, which overcomes the limitation of conventional methods, shows excellent tooth whitening efficiency and safety, and even exhibits outstanding antibacterial activity. Inspired by stomata and chloroplasts in green leaves, we have developed an integrated two-phase free radical hydrogel (TP-GEL), which integrates solid-phase and liquid-phase free radical functional components fabricated by cold plasma technology. TP-GEL demonstrated safe and ultrafast tooth-whitening effect with or without visible light, which can be more significant than that of 30% H2O2, the commonly whitening material in dental clinical practice. More importantly, we also avoid the damage to enamel, such as microhardness, roughness, surface morphology. Benefiting from free radicals, much higher antibacterial properties than commercial products (Chlorhexidine) was obtained. This research provides fundamental design criteria for the development of dual functional oral health care materials with advanced tooth whitening and antibacterial activity.