title: Fabrication of porous beta-tricalcium phosphate with microchannel and customized geometry based on gel-casting and rapid prototyping.
abstract: The tissue engineering scaffolds with three-dimensional porous structure are regarded to be beneficial to facilitate a sufficient supply of nutrients and enable cell ingrowth in bone reconstruction. However, the pores in scaffolds tend to be blocked by the cell ingrowth and result in a restraint of nutrient supply in the further side of the scaffold. An indirect approach of combining the rapid prototyping and gel-casting technique is introduced in this study to fabricate beta-tricalcium phosphate (beta-TCP) scaffolds which not only have interconnected porous structure, but also have a microchannel network inside. The scaffold was designed with customized geometry that matches the defect area, and a double-scale (micropores-microchannel) porous structure inside that is beneficial for cell ingrowth. The scaffolds fabricated have an open, uniform, and interconnected porous architecture with a pore size of 200-400 microm, and posses an internal channel network with a diameter of 600 microm. The porosity was controllable. The compressive yield strength was 4.5 MPa with a porosity of 70 per cent. X-ray diffraction analysis shows that these fabrication processes do not change the crystal structure and chemical composition of beta-TCP. With this technique, it was also possible to fabricate porous scaffolds with desired pore size, porosity, and microchannel, as well as customized geometries by other bioceramics.
authors.affiliation: State Key Lab for Manufacturing System Engineering, Xi'an Jiaotong University, Xi'an, ShaanXi, People's Republic of China.
authors.forename: X
authors.initials: X
authors.lastname: Li
authors.forename: W
authors.initials: W
authors.lastname: Bian
authors.forename: D
authors.initials: D
authors.lastname: Li
authors.forename: Q
authors.initials: Q
authors.lastname: Lian
authors.forename: Z
authors.initials: Z
authors.lastname: Jin
mesh_terms: D000818:Animals; D018786:Bone Substitutes; D002130:Calcium Phosphates / Q000737:chemistry*; D017076:Computer-Aided Design; D004285:Dogs; D005269:Femur / Q000033:anatomy & histology; D055616:Microtechnology; D016062:Porosity; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry*; D014057:Tomography, X-Ray Computed; D014961:X-Ray Diffraction
chemical_list: D018786:Bone Substitutes; D002130:Calcium Phosphates; C485817:beta-tricalcium phosphate