Multifunctional Prosthesis Surface: Modification of Titanium with Cinnamaldehyde‐Loaded Hierarchical Titanium Dioxide Nanotubes

Abstract Orthopedic prostheses are the ultimate therapeutic solution for various end‐stage orthopedic conditions. However, aseptic loosening and pyogenic infections remain as primary complications associated with these devices. In this study, a hierarchical titanium dioxide (TiO 2 ) nanotube drug delivery system loaded with cinnamaldehyde for the surface modification of titanium implants, is constructed. These specially designed dual‐layer TiO 2 nanotubes enhance material reactivity and provide an extensive drug‐loading platform within a short time. The introduction of cinnamaldehyde enhances the bone integration performance of the scaffold (simultaneously promoting bone formation and inhibiting bone resorption), anti‐inflammatory capacity, and antibacterial properties. In vitro experiments have demonstrated that this system promoted osteogenesis by upregulating both Wnt/β‐catenin and MAPK signaling pathways. Furthermore, it inhibits osteoclast formation, suppresses macrophage‐mediated inflammatory responses, and impedes the proliferation of Staphylococcus aureus and Escherichia coli. In vivo experiments shows that this material enhances bone integration in a rat model of femoral defects. In addition, it effectively enhances the antibacterial and anti‐inflammatory properties in a subcutaneous implant in a rat model. This study provides a straightforward and highly effective surface modification strategy for orthopedic Ti implants.