Papers by Author: J.H. Yoon

Abstract: To develop a suitable scaffold optimizing bone regeneration, we developed bovine bone ash derived fully connected porous HA ceramic scaffolds adopting a foaming method. They revealed excellent biocompatibility. The attached cells on the scaffolds proliferated in multi-layers with osteoblastic differentiation. The bone defects grafted with bovine bone ash derived fully interconnected porous HA ceramics having average 500 μm sized spherical pores and average 150 μm sized interconnecting interpores with average 80% porosity were favorably healed without any pathologic changes within 3 weeks. New bone ingrowth with excellent osteoconduction through the spherical pores along the inner surface was noted from 1 week after implantation. Each spherical pore was filled with hematopoietic marrow and newly formed bone which with time was well integrated with the porous HA ceramic scaffold with time. These findings suggest that the bovine bone ash-derived fully interconnected porous HA ceramic formed by foaming method can be a promising bone substitute and a scaffold for bone tissue engineering.

Abstract: As a part of the effort to develop a suitable scaffold for tissue-engineered bone regeneration, we modified calcium metaphosphate (CMP) ceramic with Na20 and evaluated its efficiency as a scaffold. We incorporate 5% Na20 into pure CMP and prepare for an average pore size of 250 or 450 µm average pore sizes. The incorporation of 5% Na2O caused reduced compressive strength and there was no change in biodegradability. The in vitro cellular attachment and proliferation rate, however, were slightly improved. The 5% Na2O-incorporated macroporous CMP ceramic-cell constructs treated with Emdogain induced ectopic bone formation more effectively than those without Emdogain treatment. These results suggest that the incorporation of 5% Na2O into pure CMP is not effective for improving the physical characteristics of pure CMP but it is positive for improving the cellular reaction and osteogenic effect with the addition of Emdogain.