title: Hydroxylapatite with substituted magnesium, zinc, cadmium, and yttrium. I. Structure and microstructure.
abstract: Hydroxylapatite (HA) was made containing magnesium, zinc, cadmium, and yttrium. Salts of these cations were added to precipitating HA; the precipitates were dried and sintered at 1100 degrees C for 1 h. Lattice parameters from X-ray diffraction spectra showed that these elements were incorporated into the apatite structure at a level of 2% added fraction of calcium in HA and up to 7% for yttrium. The densities of different substituted apatites were close to theoretical for pressed and sintered samples, which is evidence for low bulk porosity. The grain sizes of substituted apatites were smaller than those of pure HA except for cadmium-containing apatite. Surfaces of etched samples showed no second phases, whereas surfaces of unetched samples showed second phases and higher porosity than etched surfaces.
authors.affiliation: Department of Materials Science and Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180-3590, USA.
authors.forename: Celaletdin
authors.initials: C
authors.lastname: Ergun
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Webster
authors.forename: Rena
authors.initials: R
authors.lastname: Bizios
authors.forename: Robert H
authors.initials: RH
authors.lastname: Doremus
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry*; D018786:Bone Substitutes / Q000138:chemical synthesis / Q000737:chemistry; D002104:Cadmium / Q000737:chemistry; D006882:Hydroxyapatites / Q000138:chemical synthesis / Q000737:chemistry*; D008274:Magnesium / Q000737:chemistry; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D015394:Molecular Structure; D010316:Particle Size; D013499:Surface Properties; D014961:X-Ray Diffraction; D015019:Yttrium / Q000737:chemistry; D015032:Zinc / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes; D006882:Hydroxyapatites; D002104:Cadmium; D015019:Yttrium; D008274:Magnesium; D015032:Zinc