title: Osteoconduction of a stoichiometric and bovine hydroxyapatite bilayer-coated implant.
abstract: OBJECTIVE
  To impart rapid and durable osteoconductivity to implants, a commercial titanium screw implant was coated with stoichiometric hydroxyapatite (HA; 50 nm thick), and then with bovine hydroxyapatite (B-HA; 300 nm thick) using the pulsed laser deposition technique. As control specimens, a commercial implant coated with HA (20 μm thick) using the flame spraying method (sprayed implant) and a simple titanium implant (basic implant) was used.
  
  
  METHODS
  The osteoconductivities of these three types of implant, after implantation for 4-24 weeks, were histologically evaluated.
  
  
  RESULTS
  Peeling of HA from the sprayed implant was observed by scanning electron microscopic observation. In the fourth postoperative week, the bilayered implant was already closely adhered to bone. On the other hand, the basic implant was surrounded by a gap containing connective tissue. With the sprayed implant, the bone adhered to the thick HA coating.
  
  
  CONCLUSIONS
  The bilayer deposition technique supplies quick and long-term fixation of implants to bone, because the B-HA film dissolves to aid osteoconduction right immediately after implantation and the HA thin film maintains osteoconduction without dissolution. Neither of the thin-film fractures easily compared with thick coatings.
authors.affiliation: School of Biology-Oriented Science and Technology, Kinki University, Wakayama, JapanDepartment of Geriatric Dentistry, Osaka Dental University, Osaka, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Hayami
authors.affiliation: School of Biology-Oriented Science and Technology, Kinki University, Wakayama, JapanDepartment of Geriatric Dentistry, Osaka Dental University, Osaka, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Hontsu
authors.affiliation: School of Biology-Oriented Science and Technology, Kinki University, Wakayama, JapanDepartment of Geriatric Dentistry, Osaka Dental University, Osaka, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Higuchi
authors.affiliation: School of Biology-Oriented Science and Technology, Kinki University, Wakayama, JapanDepartment of Geriatric Dentistry, Osaka Dental University, Osaka, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Nishikawa
authors.affiliation: School of Biology-Oriented Science and Technology, Kinki University, Wakayama, JapanDepartment of Geriatric Dentistry, Osaka Dental University, Osaka, Japan.
authors.forename: Masanobu
authors.initials: M
authors.lastname: Kusunoki
mesh_terms: D000818:Animals; D001861:Bone Regeneration; D002417:Cattle; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D015921:Dental Implants; D004285:Dogs; D017886:Durapatite / Q000737:chemistry*; D005269:Femur / Q000601:surgery; D020007:Implants, Experimental; D007834:Lasers; D008855:Microscopy, Electron, Scanning; D013499:Surface Properties; D014025:Titanium
chemical_list: D020099:Coated Materials, Biocompatible; D015921:Dental Implants; D017886:Durapatite; D014025:Titanium