Titanium‐Based Tannic Acid/Silver/Dexamethasone Composite Coatings with Antimicrobial and Osteoinductive Functions

The increasing demand for orthopedic biomaterials, driven by aging populations, has highlighted the limitations of titanium (Ti) and Ti‐alloys, including bacterial adhesion and implant failure. To address these issues, a novel dexamethasone/tannic acid/silver composite coating (Ti/TA/Ag/Dex) is developed on titanium. Silver nanoparticles, synthesized by reducing Ag + with tannic acid, exhibit antimicrobial activity and synergistic photothermal, and photodynamic effects under near‐infrared (NIR) light, generating heat and reactive oxygen species. The coating's antibacterial performance is confirmed with a 100% sterilization rate against Escherichia coli and Staphylococcus aureus under NIR irradiation (808 nm), achieving a surface temperature of 53.4 °C with a photothermal efficiency of 32.6%. Additionally, dexamethasone (Dex) promotes osteoblast differentiation, confirmed by upregulation of Runx2 and Collagen I proteins. The coating's biocompatibility is verified through CCK‐8 and histological hematoxylin‐eosin staining. This Ti/TA/Ag/Dex composite coating effectively combines antibacterial and osteogenesis functions, offering a promising biomaterial strategy for repairing infected bone defects.