Ce-TZP/Al2O3 nanocomposite as a bearing material in total joint replacement.
The objectives of this study were to investigate the biocompatibility, phase stability, and wear properties of a newly developed Ce-TZP/Al(2)O(3) nanocomposite, as compared to conventional ceramics, and to determine whether the new composite could be used as a bearing material in total joint prostheses. In tests of mechanical properties, this composite showed significantly higher toughness than conventional Y-TZP. For biocompatibility tests, cylindrical specimens of both the Ce-TZP/Al(2)O(3) nanocomposite and monolithic alumina were implanted into the paraspinal muscles of male Wistar rats. The tissue reactions were almost the same, and at 24 weeks after implantation, thin fibrous capsules with almost no inflammation were observed around both of them. There were no significant differences in membrane thickness between the two ceramics. After hydrothermal treatment in 121 degrees C vapor for 18 h, the new composite showed complete resistance to aging degradation, whereas Y-TZP showed a phase transformation of 25.3 vol% (initial 0.4%) to the monoclinic form. According to the results of pin-on-disk tests, the wear rates of Ce-TZP/Al(2)O(3) nanocomposite and alumina were 0.55 +/- 0.04 x 10(-7) and 2.12 +/- 0.37 x 10(-7)mm(3)/Nm, respectively. The results of this study suggest that the Ce-TZP/Al(2)O(3) nanocomposite is a promising alternative ceramic component for total joint replacement.
Department of Orthopedic Surgery, Faculty of Medicine, Kyoto University, Kawahara-cho 54, Shogoin, Sakyo-ku, Japan.
Kenji
K
Tanaka
Jiro
J
Tamura
Keiichi
K
Kawanabe
Masahiro
M
Nawa
Masanori
M
Oka
Masaki
M
Uchida
Tadashi
T
Kokubo
Takashi
T
Nakamura
D000537:Aluminum Oxide / Q000008:administration & dosage / Q000494:pharmacology; D000818:Animals; D001672:Biocompatible Materials / Q000008:administration & dosage / Q000494:pharmacology / Q000592:standards; D002448:Cell Adhesion; D002563:Cerium / Q000008:administration & dosage / Q000494:pharmacology; D003188:Composite Resins / Q000008:administration & dosage / Q000737:chemistry* / Q000494:pharmacology; D007595:Joint Prosthesis / Q000592:standards*; D008297:Male; D008422:Materials Testing; D019563:Mechanics; D009132:Muscles / Q000166:cytology / Q000276:immunology; D019919:Prosthesis Implantation; D051381:Rats; D017208:Rats, Wistar; D015040:Zirconium / Q000008:administration & dosage / Q000494:pharmacology
D001672:Biocompatible Materials; C475766:Ce-TZP-Al2O3; D003188:Composite Resins; D002563:Cerium; D015040:Zirconium; D000537:Aluminum Oxide