Fabrication of Bone Substitutes by the Sponge Replica Method
Calcium phosphate bone substitutes are widely used for providing support for the in-growth of hard tissue in various medical applications (e.g., dental, orthopedic). Recently, research involving bone substitutes with interconnected open pore structures has focused on improving the mechanical properties of the substitutes and modifying their surfaces with proteins (e.g., collagen, bone morphogenetic protein) to induce early bone formation. In particular, it is highly desirable to develop a functional gradient-structured bone substitute that has the potential to control the bioresoption rate. A porous BCP scaffold was fabricated by the sponge replica method using a PU sponge. The sponge was dip coated three times followed by oven drying, burning out, and microwave sintering. Several approaches were used to fabricate a functional gradient scaffold. TCP was synthesized using the sol-gel process, and it infiltrated into the pore channel that formed after the burning out of the PU sponge. X-ray diffraction analysis characterized the phase identification of the BCP scaffold. Microstructures of the composites were observed using scanning electron microscopy.
Jian-Feng Nie and Allan Morton
M. S. Kim et al., "Fabrication of Bone Substitutes by the Sponge Replica Method", Materials Science Forum, Vols. 654-656, pp. 2245-2248, 2010