Three-dimensional morphology and mechanics of bone scaffolds fabricated by rapid prototyping

Alpha-beta-tri-calcium phosphate is a promising biomaterial to fabricate scaffolds for the reconstruction of osseous defects. In the present study, we demonstrate that three-dimensional printing allows tailoring the porosity and the mechanical properties of nature-analogue designed scaffolds. Sophisticated software tools applied to the acquired tomography data were used to characterize the printing quality and the porosity by means of the distance transform, the radial density distribution and the accessibility by virtual spheres. Analyzing the stress-strain curves of the scaffolds, the Young's modulus and the ultimate compressive strength were obtained. To reach mechanical properties comparable to those of jaw bone, the scaffolds were treated with phosphoric acid. Depending on the design, the compressive strength of the bone scaffolds lies between 30 and 60 MPa and their Young's modulus is between 50 and 140 MPa. Hence, prototypes for clinical trials can be fabricated in near future.