| 摘要 |
Shape-memory biodegradable and absorbable materials which make it possible to easily treat vital tissues by suture, anastomosis, ligation, fixation, reconstitution, prosthesis, etc. without causing burn. These materials never induce halation in MRI or CT and never remain in vivo. Such a shape-memory biodegradable and absorbable material is a material made of a molded article of lactic acid-based polymer and can be recovered to the original shape without applying any external force thereto but heating to a definite temperature or above. It is obtained by deforming a molded article (a primary molded article) made of a lactic acid-based polymer and having a definite shape into another molded article (a secondary molded article) having another shape at a temperature higher than the glass transition temperature thereof but lower than the crystallization temperature thereof (or 100 DEG C when the molded article has no crystallization temperature) and then fixing said molded article to the thus deformed shape by cooling it as such to a temperature lower than the glass transition temperature. When this material is heated to the above-mentioned deformation temperature or above, it is immediately recovered to the original shape. The lactic acid-based polymer is hydrolyzed and absorbed in vivo. |
