Papers by Keyword: αTCP

Abstract: This study aims to improve the handling property of alpha-tricalcium (αTCP) cement. In order to improve the handling property, the effect of γ-poly-glutamic acid (γPGA) as a chelating agent was studied. γPGA is water soluble, biodegradable, nontoxic, and edible material. γPGA contains carboxyl group, so the chelating effect between Ca²⁺ ions released from calcium phosphate cement and carboxyl group of γPGA is prospected when it mixed with αTCP based cement. The results obtained in this study clearly demonstrated that the addition of γPGA into the αTCP cement was highly effective in controlling the handling property of αTCP cement.

Abstract: As excellent scaffolds for cultivating bone cells, porous beads of bioactive ceramics such as HAp, TCP are considered to be promising. HAp and α-TCP are well known as non-toxic bioceramics to human cells, but their behavior in living body fluid are different. HAp is bioactive material which has both high strength and better tissue-adhesive properties, but that is not readily absorbed by the human body. On the contrary, α-TCP is highly bioabsorbable; it is quickly absorbed by the body, and, therefore, disappears before bone is completely replaced. To realize a composite which has suitable solubility in living body fluid, α-TCP/ HAp functionally graded porous beads were fabricated by the method of spheroidization in liquid nitrogen. This type of composite maintains the function of scaffold with sufficient strength up to growth of new bone, and after the growth, it is expected to absorbed completely in the body. In the present study, ceramic beads with α-TCP at the center were fabricated and coated with a functionally graded layer of HAp. By controlling the thickness of HAp layer, which could be realized by changing time of hydrolytic reaction, the absorption rate into the body would be easily controlled. In addition, to accelerate the formation of porous structure, some acid solutions were used to dissolve the beads surface and to penetrate pores toward inside of the beads. Observed surface and inner structure by SEM, also the measured change in absorption rate will be presented.