title: Electrical polarization of plasma-spray-hydroxyapatite coatings for improvement of osteoconduction of implants.
abstract: We have established the electrical polarization method of hydroxyapatite (HA) coatings (HAC) for clinical use, such as dental and orthopedic implants. The HAC examined in the current study was prepared in titanium substrates by plasma spraying of beta-tricalcium phosphate (TCP) powders followed by hydrothermal treatment. The prepared HAC consisted of a single phase of HA, because the starting TCP phase was completely transformed to the HA phase during the posthydrothermal treatment. Polarization was carried out at the elevated temperature of 400 degrees C under a d.c. field of 1 kV . cm(-1). The electrical measurements showed that the stored charges of the polarized HAC were greater than the reported value of the sintered ceramic HA. The enhanced bioactivity of the polarized HAC was demonstrated using 1.5 simulated body fluid (SBF). The crystal growth from the SBF solution was accelerated on the negatively charged surface in comparison with the untreated HAC. Similar to the polarized ceramic HA, the current results confirmed that the bioactivity of HAC would be effective for improving the initial fixation by polarization.
authors: Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda, Tokyo 101-0062, Japan.
authors: Reiko
authors: R
authors: Kato
authors: Satoshi
authors: S
authors: Nakamura
authors: Keiich
authors: K
authors: Katayama
authors: Kimihiro
authors: K
authors: Yamashita
mesh_terms: D002130:Calcium Phosphates / Q000737:chemistry*; D002516:Ceramics / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D003460:Crystallization; D006358:Hot Temperature; D008855:Microscopy, Electron, Scanning; D019736:Prostheses and Implants; D014025:Titanium / Q000737:chemistry*
chemical_list: D002130:Calcium Phosphates; D020099:Coated Materials, Biocompatible; D014025:Titanium; C018392:tricalcium phosphate