저탄성계수 타이타늄 신합금 설계 및 생체적합성 평가

Alloy design and in-vitro assessment of biocompatibilities of novel titanium alloys with low elastic modulus were studied. A contour map of elastic modulus which enables to predict low modulus alloy composition was established by using electron theory. Ti-30Ta-10Nb-10Zr, Ti-40Ta-10Nb-10Zr and Ti-40Ta10Nb-4Sn alloys were designed by using the contour map of elastic modulus, and Young`s moduli of those alloys were as low as around 60 GPa. Anodic polarization curves for the alloys represented that corrosion resistance of Ti-40Ta-10Nb-10Zr and Ti-40Ta-10Nb-10Zr was comparable to those of biomedically approved CP Ti and Ti-6Al-4V in simulated body fluid(Hank`s solution) at 37℃, while corrosion resistance of Ti-40Ta-10Nb-4Sn was inferior to those of CP Ti and Ti-6Al-4V. MTT assay with osteoblast-like cells(MG63) showed that the extent of initial cell attachment was similar in all alloys, while cell proliferation of Ti-40Ta-l0Nb10Zr and Ti-40Ta-10Nb-4Sn alloys was more sluggish than those in CP Ti and Ti-6Al-4V. It was therefore realized that the selection of alloying elements for designing low modulus alloys should be considered in the viewpoint of cell growth as well as cytotoxicity.