Preparation, characterization, in vitro bioactivity and rBMSCs responses to tantalum pentoxide/polyimide biocomposites for dental and orthopedic implants

Polyimide (PI) may become a promising biomaterial for dental and orthopedic application due to its high mechanical strength, good biocompatibility and bio-stability as well as modulus of elasticity similar to the bone of human body. In this study, bioactive tantalum pentoxide (Ta2O5, TO)/polyimide (PI) composites (TPC) were fabricated by blending modification through a process of cold-pressing and sintering. The results revealed that the compressive strength, thermal stability, surface roughness, hydrophilicity and surface energy of TPC were significantly enhanced with the increase of TO content. Moreover, apatite mineralization of TPC in simulated body fluid (SBF) was obviously improved, in which TPC with TO of 50 wt% content (TPC50) displayed the best bioactivity. Furthermore, the cellular responses (adhesion, proliferation and differentiation) of rat bone mesenchymal stem cells (rBMSCs) to TPC were obviously upregulated with the increase of TO content. The results demonstrated that the TO content in the composites remarkably affected not only physical-chemical properties but also the cells behaviors. It can be suggested that TPC50 with improved surface properties and bioactivity as well as good cytocompatibility would have great potential and prospect for dental and orthopedic applications.