title: Effect of highly dispersed yttria addition on thermal stability of hydroxyapatite.
abstract: The capability of the colloidal method to produce yttria (Y(2)O(3)) dispersed hydroxyapatite (HA) has been investigated as an alternative method to the conventional method of mechanical mixing and sintering for developing HA-based materials that could exhibit controllable and enhanced functional properties. A water based colloidal route to produce HA materials with highly dispersed Y(2)O(3) has been applied, and the effect of 10 wt.% Y(2)O(3) addition to HA investigated by thermal analysis, X-ray diffraction and Fourier transform infrared spectroscopy. These measurements evidence a remarkable effect of this Y(2)O(3) addition on decomposition mechanisms of synthetic HA. Results show that incorporation of Y(2)O(3) as dispersed second phase is beneficial because it hinders the decomposition mechanisms of HA into calcium phosphates. This retardation will allow the control of the sintering conditions for developing HA implants with improved properties. Besides, substitution of Ca(2+) with Y(3+) ions appears to promote the formation of OH(-) vacancies, which could improve the conductive properties of HA favorable to osseointegration.
authors.affiliation: Instituto de Cerámica y Vidrio, CSIC, C/Kelsen 5, Madrid 28049, Spain. Electronic address: pparente@icv.csic.es.
authors.forename: P
authors.initials: P
authors.lastname: Parente
authors.affiliation: Departamento de Física, Universidad Carlos III de Madrid, Avda. Universidad 30, Leganés 28911, Spain.
authors.forename: B
authors.initials: B
authors.lastname: Savoini
authors.affiliation: Instituto de Cerámica y Vidrio, CSIC, C/Kelsen 5, Madrid 28049, Spain.
authors.forename: B
authors.initials: B
authors.lastname: Ferrari
authors.affiliation: Departamento de Física, Universidad Carlos III de Madrid, Avda. Universidad 30, Leganés 28911, Spain.
authors.forename: M A
authors.initials: MA
authors.lastname: Monge
authors.affiliation: Departamento de Física, Universidad Carlos III de Madrid, Avda. Universidad 30, Leganés 28911, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Pareja
authors.affiliation: Instituto de Cerámica y Vidrio, CSIC, C/Kelsen 5, Madrid 28049, Spain.
authors.forename: A J
authors.initials: AJ
authors.lastname: Sanchez-Herencia
mesh_terms: D002118:Calcium / Q000737:chemistry; D004355:Drug Stability; D017886:Durapatite / Q000737:chemistry*; D006358:Hot Temperature; D053758:Nanoparticles / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D015019:Yttrium / Q000737:chemistry*
chemical_list: D015019:Yttrium; D017886:Durapatite; D002118:Calcium; C091417:yttria