In Vitro Investigation of the Biocompatibility of 6 Different High-Performance Resin-Based Materials for Bone Augmentation and Reconstruction.

Introduction: Reconstructive surgery often addresses severe bone defects that impact patients' lives. While microvascular bone transfer is standard, it has drawbacks. Thus, the focus shifts to using alloplastic grafts, avoiding donor sites. This study evaluates the biocompatibility of generatively printed high-performance resins.

Materials and methods: Six printed materials were compared with titanium scaffolds: native PEEK (poly-ether-ether-ketone) and native PEKK (poly-ether-ketone-ketone) as well as the surface-modified materials MBTg (Mimicking Bone Technology) PEEK, BCP-filled PEEK, 4h-argon-etched PEKK, and So_PPSU [polyphenylsulfone with barium sulfate (BaS8O4)]. The scaffolds were CAD/CAM manufactured and individually dimensioned using Fused Layer Manufacturing. Biocompatibility was assessed through cytotoxicity, osteoblast viability, and differentiation assays. Osteoblast colonization and adhesion were examined using fluorescence and electron microscopy.

Results: All materials were noncytotoxic (P<0.05). So_PPSU exhibited the highest cell proliferation rates. MBTg PEEK, BCP-filled PEEK, and native PEKK also showed significant increases over time (P<0.05). Alkaline phosphatase activity increased for all materials, with 4h-argon-etched PEKK, MBTg PEEK, and BCP-filled PEEK showing the greatest increases. Microscopy validated these findings.

Conclusions: The tested materials were noncytotoxic, with MBTg-functionalized PEEK, 4h-argon-etched PEKK and BCP-filled PEEK showing the best biocompatibility. Furthermore, the study demonstrated the feasibility of a time-saving 3D printing process for the reproducible production of customized and functionally designed medical products.