Gradient 3D printed PEEK with nano-coating facilitates rapid manufacturing with dual enhanced osteogenic and anti-bacterial property.

Artificial prosthesis and implants in oral and maxillofacial surgery are in urgent need of innovation. Plenty of bioactive agents have been added to PEEK, whereas complex processing technique hinders clinical translation. To break through the limitation, this study first applied gradient 3D printing technique to incorporate hydroxyapatite and nano-Ag into the functional coating on surface of PEEK. The advantage of gradient 3D printing facilitates rapid manufacturing and customization with minimum cost, which presents a significant advance toward clinical application. Compared to traditional PEEK, the dual enhancement of osteogenesis and anti-bacterial property were testified in vitro and in vivo. In addition, the bio-mechanism behind was first revealed to bridge the gap between theory and practice. Hydroxyapatite activated mTOR signaling pathway to enhance osteogenesis, and nano-Ag showed prominence in FoxO signaling pathway to mediate anti-bacterial property, while triggered ROS reaction and activated PPARγ pathway, minorly hindering osteointegration process. The novel gradient 3D printed PEEK with nano-coating could be rapidly manufactured with micro-structural surface, bone-like elastic modulus and excellent osteogenesis and anti-bacterial property, which has great potential for clinical translation in the field of oral and maxillofacial surgery.