Using Surface Modification to Enhance Biocompatibility of Polyetherketoneketone Implant Surface

Objectives: Polyetherketoneketone (PEKK) shows potential for dental implant applications. Our previous research successfully utilized sulfonation and atmospheric plasma treatment to prepare a superhydrophilic 3D porous structure on PEKK. This structure exhibits favorable vascularization and initial bone cell growth. However, this PEKK surface remains bioinert and requires further improvement of osseointegration. This study aimed to further bioactivate the inert PEKK surface using a biomolecular coating (specifically grafting type I collagen) through natural crosslinker.
Methods: Type I collagen was grafted onto the superhydrophilic porous PEKK surface using a natural crosslinker. Following surface modification, the material surface morphology, roughness, hydrophilicity, and functional groups were analyzed. In vitro cell response assessments included vascularization, osteogenic activity, and osteoclastic resorption. The number of sample size for each test group was at least three. Student t-test was used to statistically analyze the test reults, with p < 0.05 as significance.
Results: We applied the sulfonation and atmospheric plasma treatment to prepare a superhydrophilic 3D porous structure on the PEKK surface. Subsequently, we grafted type I collagen on the superhydrophilic 3D porous structure using natural crosslinker such as procyanidin, epigallocatechin gallate (EGCG), or genipin. These modified surfaces significantly promoted angiogenesis and regulated bone remodeling capabilities (i.e., inhibiting osteoclastic resorption and enhancing osteogenic activity).
Conclusions: This study introduces a simple surface treatment method designed to enhance the potential of PEKK in dental implants. To advance this research, further exploration of its biological response mechanisms and in vivo testing on animals will be essential.