Modified Zno Composite Films For Antibacterial Oral Treatment Instruments

Gaps between orthodontic brackets, implant healing abutments, and oral tissues often promote dental plaque biofilm accumulation, leading to caries and periodontal diseases. To address these problems, we developed an antibacterial surface coating for oral therapeutic devices by modifying zinc oxide nanoparticles (ZnO NPs) with polydopamine (PDA) and further assembling them with the film-forming protein zein into ZnO@PDA/Zein composite films. The adhesion and sustained-release properties of the membranes were evaluated via nanoscratch testing and in vitro release assays, while biocompatibility and antibacterial efficacy were assessed using CCK-8 cytotoxicity assays and colony-forming unit (CFU) enumeration. Results demonstrated that The films had long-term sustained release and adhesion effects on oral treatment instruments. At a ZnO@PDA concentration of 0.6 mg/mL, the membranes inhibited Staphylococcus aureus and Streptococcus mutans with negligible cytotoxicity. Increasing the concentration to 1.2 mg/mL extended antibacterial activity to Escherichia coli. These findings highlighted the dual functionality of ZnO@PDA/Zein membranes in biofilm prevention and biocompatibility, offering a promising strategy for antimicrobial surface engineering of oral medical devices.