title: In vitro dissolution and corrosion study of calcium phosphate coatings elaborated by pulsed electrodeposition current on Ti6Al4V substrate.
abstract: Calcium-deficient hydroxyapatite (Ca-def-HAP) coatings on titanium alloy (Ti6Al4V) substrates are elaborated by pulsed electrodeposition. In vitro dissolution/precipitation process is investigated by immersion of the coated substrate into Dulbecco's Modified Eagle Medium (DMEM) from 1 h to 28 days. Calcium and phosphorus concentrations evolution in the biological liquid are determined by Induced Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) for each immersion time. Physical and chemical characterizations of the coating are performed by scanning electron microscopy (SEM) associated to Energy Dispersive X-ray Spectroscopy (EDXS) for X-ray microanalysis. Surface modifications are investigated by an original method based on the three-dimensional reconstruction of SEM images (3D-SEM). Moreover, corrosion measurements are carried out by potentiodynamic polarization experiments. The results show that the precipitation rate of the Ca-def HAP coating is more pronounced in comparison with that of stoichiometric hydroxyapatite (HAP) used as reference. The precipitated bone-like apatite coating is thick, homogenous and exhibits an improved link to the substrate. Consequently, the corrosion behaviour of the elaborated prosthetic material is improved.
authors.affiliation: INSERM UMR-S 926, IFR 53, URCA, 21 rue Clément Ader, BP 138, 51685 Reims Cedex 02, France. richard.drevet@univ-reims.fr
authors.forename: R
authors.initials: R
authors.lastname: Drevet
authors.forename: F
authors.initials: F
authors.lastname: Velard
authors.forename: S
authors.initials: S
authors.lastname: Potiron
authors.forename: D
authors.initials: D
authors.lastname: Laurent-Maquin
authors.forename: H
authors.initials: H
authors.lastname: Benhayoune
mesh_terms: D000497:Alloys; D002118:Calcium / Q000737:chemistry; D002130:Calcium Phosphates / Q000737:chemistry*; D003343:Corrosion; D017886:Durapatite / Q000737:chemistry; D004563:Electrochemistry / Q000379:methods*; D004577:Electron Probe Microanalysis; D004595:Electroplating; D004867:Equipment Design; D066298:In Vitro Techniques; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning / Q000379:methods; D046529:Microscopy, Electron, Transmission / Q000379:methods; D010758:Phosphorus / Q000737:chemistry; D013054:Spectrophotometry, Atomic / Q000379:methods; D013997:Time Factors; D014025:Titanium / Q000737:chemistry*
chemical_list: D000497:Alloys; D002130:Calcium Phosphates; C031462:titanium alloy (TiAl6V4); D010758:Phosphorus; D017886:Durapatite; C020243:calcium phosphate; D014025:Titanium; D002118:Calcium