3D printed porous PEEK scaffolds with stable and durable gelatin composite hydrogel coating loaded Yoda1 for in vivo osseointegration.

Polyetheretherketone (PEEK) has emerged as a promising material for bone substitution; however, its limited osseointegration hinders its clinical applications. This research employs a porous structural design alongside surface modification techniques to improve the osseointegration properties of PEEK. Porous PEEK scaffolds were fabricated via 3D printing technology, followed by the application of a stable coating of Yoda1-loaded methacrylated gelatin (GelMA) on their surfaces. After modification, the hydrophilicity of the PEEK scaffolds was considerably improved, and the GelMA coating facilitated the sustained release of Yoda1. In vitro experiments demonstrated that the modified surfaces promoted cell proliferation and adhesion, facilitated angiogenesis, and enhanced osteoblast differentiation and mineral deposition. Furthermore, porous PEEK scaffolds were implanted into the femoral condyles of SD rats for 6 weeks to evaluate in vivo osseointegration The results showed that the tailored three-dimensional porous structure, along with the Yoda1-loaded GelMA coating, promoted bone ingrowth and enhanced osseointegration within the scaffold. This study offers a viable strategy for enhancing PEEK osseointegration through a combination of structural design and surface modification, and introduces new avenues for the application of Yoda1 in bone tissue engineering.