Beneficial Effect of TaON-Ag Nanocomposite Titanium on Antibacterial Capacity in Orthopedic Application

PURPOSE: In this study, a novel oxygenated nanocomposite thin film, TaON-Ag, was investigated in vitro and in vivo to evaluate its biocompatibility and antibacterial ability. MATERIAL AND METHODS: The antibacterial ability of TaON-Ag nanocomposite-coated titanium (Ti) was evaluated using the Kirby-Bauer disk diffusion susceptibility test. The effects of TaON-Ag nanocomposite-coated metal on osteogenesis were further evaluated in an in vitro osteogenic culture model with rat marrow-derived mesenchymal stem cells (rMSCs). Furthermore, titanium rods coated with TaON-Ag were implanted into a rat femur fracture model either with or without osteomyelitis to investigate the effects of TaON-Ag in osteogenesis. RESULTS: The TaON-Ag-coated Ti exhibited an effective antibacterial effect against Staphylococcus aureus, coagulase-negative Staphylococcus, and the Gram-negative strains Escherichia coli and Pseudomonas aeruginosa. Using an osteogenic culture with rMSCs and a rat femoral fracture model, the TaON-Ag-coated Ti did not interfere with the ossification of rMSCs in vitro or during fracture healing in vivo. Field-emission scanning electron microscopy (FE-SEM) revealed that coating with TaON-Ag could inhibit pathogen adhesion and biofilm formation in both Staphylococcus aureus and Escherichia coli. CONCLUSION: Using the proposed novel oxygenation process, TaON-Ag nanocomposite-coated Ti yielded robust biocompatibility and antibacterial ability against common microorganisms in orthopedic infections, thereby demonstrating potential for use in clinical applications.