Abstract
Bone graft materials with interconnected porous structure have paid much attention because the porous structure allows cells to penetrate into the bone grafts and may enhance its bone replacement. In this study, interconnected porous artificial bone grafts were fabricated by employing setting mechanism of brushite forming cement. Calcium carbonate or calcium phosphate granules with a few hundred micro meters in size were reacted with acidic calcium phosphate solution to obtain the bridging between the granules due to the precipitation of brushite crystals on the granular surface. In the case of granules containing carbonate ions such as calcium carbonate, external pressure to the piling of the granules in the mold was needed to close the granules each other during the reaction since a generation of CO_2 gas due to the reaction prevented the interlocking of precipitated brushite crystals at the interface between granules. Histological analysis obtained from rabbit's tibia with implanted porous specimens indicated that surrounding tissues can be penetrated into the interconnected porous structure and also new bone can be observed inside of the pores. Therefore, we concluded that the interconnected porous artificial bone grafts fabricated using granular binding method due to the precipitation of brushite is expected to be useful as an artificial bone substitute because of faster bone replacement due to the interconnected porous structure and the chemical composition.
