title: Development of calcium phosphate based functional gradient bioceramics.
abstract: A functional gradient bioceramic that can function gradually with respect to body tissue was studied by changing the composition of calcium phosphate gradually from the surface to the inside. Diamond powder was spread on the surface of compact hydroxyapatite (HA) powder and fired at 1280 degrees C under reduced pressure, followed by firing under atmospheric conditions. The sintered body thus prepared was dense and alpha-tricalcium phosphate (alpha-TCP: alpha-Ca3(PO4)2) was found on its surface. The content of alpha-TCP gradually decreased with increasing depth from the surface. In contrast, the content of HA increased with increasing depth from the surface. The gradient ratio of alpha-TCP and HA depends on the firing time for each condition, i.e. reduced or atmospheric pressure. The alpha-TCP formation was ascribed to the decomposition of HA due to the spontaneous combustion of diamond powder.
authors.affiliation: Department of Dental Engineering, School of Dentistry, Tokushima University, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Kon
authors.forename: K
authors.initials: K
authors.lastname: Ishikawa
authors.forename: Y
authors.initials: Y
authors.lastname: Miyamoto
authors.forename: K
authors.initials: K
authors.lastname: Asaoka
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry*; D002516:Ceramics / Q000737:chemistry*; D018130:Diamond / Q000737:chemistry; D017886:Durapatite / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D011208:Powders; D019736:Prostheses and Implants; D014961:X-Ray Diffraction
chemical_list: D001672:Biocompatible Materials; D002130:Calcium Phosphates; D011208:Powders; C485828:alpha-tricalcium phosphate; C485830:tetracalcium phosphate; C485838:calcium phosphate, monobasic, anhydrous; D018130:Diamond; D017886:Durapatite; C020243:calcium phosphate; C485829:calcium phosphate, dibasic, anhydrous