Three-in-one synergistic therapy for tooth whitening and biofilm eradication using Cu-doped Bi2WO6

Abstract

Biofilm-associated dental diseases and tooth discoloration have posed a great threat to public oral health in recent years. However, there are few effective strategies with negligible side effects to address these issues. Herein, a safe, efficient, and non-destructive tooth whitening and anti-bacterial strategy is developed through a Cu-doped Bi₂WO₆-based three-in-one synergistic therapy, which includes photodynamic, sonodynamic, and Fenton-like reaction-mediated chemodynamic therapies. The results indicate that the Cu element is homogeneously doped in the whole Bi₂WO₆ substrate and more oxygen vacancies can be produced owing to the substitution of Bi(III) by Cu(II). The degradation of the common food colorant indigo carmine indicates that the three-in-one synergistic treatment exhibits an excellent degradation efficiency (99.7%), which is much higher than that of other single therapies. Teeth stained with black tea or coffee were evidently whitened by the three-in-one synergistic treatment with Cu-doped Bi₂WO₆. The anti-bacterial experiments using the three-in-one synergistic treatment showed much higher inhibitory effects than other methods for the representative caries-causing S. mutans. In addition, negligible enamel destruction and cytotoxicity caused by Cu-doped Bi₂WO₆ during the synergistic treatment was observed. The mechanism evaluation demonstrated that Cu-doped Bi₂WO₆ under synergistic treatment shows a higher separation efficiency of carriers and more ROS-producing efficiency than that under single-mode treatment. Considering the extensively adopted ultrasonic electric tooth brush and LED curing light used in dentistry, developing three-in-one synergistic therapy-based products for tooth whitening and antibacterial function could have great potential for the future oral health care.