Systematic characterization of 3D-printed PCL/β-TCP scaffolds for biomedical devices and bone tissue engineering: influence of composition and porosity.

This work aims at providing guidance through systematic experimental characterization, for the design of 3D printed scaffolds for potential orthopaedic applications, focusing on fused deposition modeling (FDM) with a composite of clinically available polycaprolactone (PCL) and β-tricalcium phosphate (β-TCP). First, we studied the effect of the chemical composition (0% to 60% β-TCP/PCL) on the scaffold's properties. We showed that surface roughness and contact angle were respectively proportional and inversely proportional to the amount of β-TCP, and that degradation rate increased with the amount of ceramic. Biologically, the addition of β-TCP enhanced proliferation and osteogenic differentiation of C3H10. Secondly, we systematically investigated the effect of the composition and the porosity on the 3D printed scaffold mechanical properties. Both an increasing amount of β-TCP and a decreasing porosity augmented the apparent Young's modulus of the 3D printed scaffolds. Third, as a proof-of-concept, a novel multi-material biomimetic implant was designed and fabricated for potential disk replacement.