|Budget Amount *help
¥1,900,000 (Direct Cost : ¥1,900,000)
Fiscal Year 1999 : ¥800,000 (Direct Cost : ¥800,000)
Fiscal Year 1998 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1997 : ¥600,000 (Direct Cost : ¥600,000)
As a filler for the bone defect, in making the chitin chitosan to be a raw material, carboxymethyl chitin-hydroxyapatite complex with the network structure was produced. In addition, bFGF impregnation CM chitin HA was also produced considering using CM chitin HA as Drug delivery system.
These new material were examined on the aptitude as a bone filler.
In present examination, the degree of the cross-link of the complex by a heat seemed to be insufficient. The material was comparatively absorbed in vivo since early stage, when it was implanted in tibia of the rabbit. It is considered that therefore, this complex does not inhibit the osteogenesis. In the meantime, the complex was rapidly absorbed in the experiment which transplanted the CM chitin in the radius bone defect model of the rabbit. And, non-infectious inflammation of the round cell invasion occurred, since the runoff of the bFGF has been early generated. As these results the osteogenesis was slow, when the complex was transplanted in the bone.
Since the solubility is high, the chitin chitosan has made that it is used for the organism with being difficult until now. Then, we developed a filler of the poor solubility using the heat cross-link technology.
When the bone defect is comparatively small, absorption rate of the complex was moderate, and the osteogenesis was observed from the peripheral part. However, the sufficient osteogenesis was not observed for large bone defect of the long bone, since the bone resorption is early.
Therefore, it is necessary to improve the control method of absorption rate in vivo in future.
It is expected that this complex becomes a safe and effective organization filler for the organism, if the control method of absorption rate is improved.