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

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, we constructed a hierarchical titanium dioxide nanotube drug delivery system loaded with cinnamaldehyde for the surface modification of titanium implants. These specially designed dual-layer titanium dioxide nanotubes enhance material reactivity and provide an extensive drug-loading platform within a short time. The introduction of cinnamaldehyde enhanced 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 inhibited osteoclast formation, suppressed macrophage-mediated inflammatory responses, and impeded the proliferation of Staphylococcus aureus and Escherichia coli. In vivo experiments showed that this material enhances bone integration in a rat model of femoral defects. In addition, it effectively enhanced 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. This article is protected by copyright. All rights reserved.