형상기억합금과 생체재료로서의 이용

This review of the literatures was done to find out the properties of shape memory alloy, the fields of its use and the biocompatibility of Nitinol alloy. The shape memory effect is the phenomenon that the alloy deformed below the transformation temperature returns to its original shape as the temperature rises, and the alloy that has this effect is called shape memory alloy. Although several alloy systems having this effect have been known, it is Ni-Ti alloy that is available as a biomaterial. Nickel possesses cytotoxicity, tissue irritability and carcinogenicity. But being mixed with titanium, it is covered with homogenous and strong passive state titanium oxide layer. So, its cytotoxicity is masked. Nitinol alloy has represented good biocompatibility in animal experiments, and it can be used in human body. This alloy is used as several ways in the medical field. In dentistry, it is used as orthodontic wire, blade implant and so on. But the research for its use as biomaterial is insufficient, so further investigation is required. i