TITLE:
Influence of Alloy Elements on the Osteoconductivity of Anodized Ti-29Nb-13Ta-4.6Zr Alloy
AUTHORS:
Dai Yamamoto, Atsushi Waki, Kensuke Kuroda, Ryoichi Ichino, Masazumi Okido, Masato Ueda, Masahiko Ikeda, Mitsuo Niinomi, Azusa Seki
KEYWORDS:
Ti-29Nb-13Ta-4.6Zr; Anodizing; Titanium Dioxide; Alloy Element; Hydrophilicity; Osteoconductivity
JOURNAL NAME:
Journal of Biomaterials and Nanobiotechnology,
Vol.4 No.3,
June
26,
2013
ABSTRACT:
Anodizing is expected to be an effective method
to improve the osteoconductivity of the Ti-29Nb-13Ta-4.6Zr (TNTZ) alloy because
the bioactivity of anodized Ti is good. However, it is not known how the alloy
elements influence the surface roughness, composition, hydrophilicity, and
osteoconductivity of the anodized film on the Ti alloy. In this study, we
investigated the effects of anodizing on the surface properties and the
osteoconductivity of the anodized TNTZ alloy, focusing on the functions of the
individual alloy elements. The anodized
oxides of the Nb, Ta, and Zr metals were hydrophobic
at all the voltages applied, in contrast to the anodized oxide of Ti. As well
as pure Ti, a TiO2-based oxide film formed on TNTZ after anodizing.
However, the oxide film also contained large amounts of Nb species and the
molar Nb/Ti ratio in the TNTZ alloy was high, which makes the surface more
hydrophobic than the anodized oxide on Ti. In
vivo tests showed that the osteoconductivity of the TNTZ alloy was
sensitive to both its surface roughness and hydrophilicity. When the TNTZ alloy
was anodized, the process increased either the surface hydrophobicity or the surface roughness at the voltage used in this study.
These changes in the surface properties did not improve its osteoconductivity.