Bone-bonding ability of a hydroxyapatite coated zirconia-alumina nanocomposite with a microporous surface.
Using a combination of hydroxyapatite (HA) coating and microporous surface treatment, bone-bonding ability was given to composites of ceria-stabilized tetragonal zirconia and alumina (CZA), which possesses excellent mechanical and wear properties and phase stability. Four types of CZA plates (2 x 10 x 15 mm3) were prepared for this study, which were CZA with a polished surface (group 1), a microporous surface prepared by hydrofluoric acid and heat treatment (group 2), a microporous surface with a submicron HA coating prepared by alternately soaking the plate from group 2 in aqueous CaCl2/HCl and Na2HPO4 solutions (group 3), and a microporous surface with a 4-microm HA coating prepared by the biomimetic method, where the plates from group 3 were soaked in simulated body fluid (group 4). Plates were implanted into rabbit tibia, and after 4, 8, and 16 weeks, tensile testing and histological examination of the bone-implant interface were conducted. At 4 weeks, group 4 had superior bone-bonding ability compared with other implants, which was maintained at the later postimplantation times. This HA-coated CZA with a microporous surface has the possibility of clinical use as a bearing material in cementless joint prostheses or as a load-bearing bone substitute.
Takemoto
M
M
Department of Orthopaedic Surgery, Graduate School of Medicine, Kyoto University, Shogoin, Kawahara-cho 54, Sakyo-ku, Kyoto 606-8507, Japan. m.take@kuhp.kyoto-u.ac.jp
Fujibayashi
S
S
Neo
M
M
Suzuki
J
J
Kokubo
T
T
Nakamura
T
T
D000537:Aluminum Oxide; D000818:Animals; D001842:Bone and Bones; D017886:Durapatite; D008297:Male; D008855:Microscopy, Electron, Scanning; D036103:Nanotechnology; D011817:Rabbits; D013499:Surface Properties; D014961:X-Ray Diffraction; D015040:Zirconium
D017886:Durapatite; D015040:Zirconium; D000537:Aluminum Oxide; C028541:zirconium oxide