Fabrication of self-setting β-tricalcium phosphate granular cement

Bone defect reconstruction would be greatly improved if β-tricalcium phosphate (β-TCP) granules had the ability to self-set without sacrificing their osteoconductivity potential. This study aimed to identify a method to permit β-TCP self-setting whilst maintaining good osteoconductivity. When mixed with acidic calcium phosphate solution, β-TCP granules were found to readily set, forming a fully interconnected porous structure. On mixing, dicalcium phosphate dihydrate crystals formed on the surface of β-TCP granules, bridging the granules and resulting in the setting reaction. The setting time of the β-TCP granular cement (β-TCP GC) was approximately 1 min and its mechanical strength, in terms of diametral tensile strength, was approximately 0.8 MPa. The β-TCP GC and β-TCP granules both showed the same level of osteoconductivity within rat calvaria bone defects. At 2 and 4 weeks post-implantation, new bone formation was comparable between the two β-TCP based bone substitutes. We conclude that β-TCP GC has excellent potential for use as a cement in bone defect reconstruction.