M A Lopez-Heredia1, G Legeay, C Gaillard, P Layrolle. 1. INSERM, U791, Laboratoire d'Ingénierie Ostéoarticulaire et Dentaire, Faculté de chirurgie dentaire, Université de Nantes, 1 Place Alexis Ricordeau, 44042 Nantes, France.
Abstract
Titanium and its alloys, when treated in alkali solutions, are able to form calcium phosphate coatings on their surface after immersion in supersaturated solutions. In this study, the surfaces of titanium alloy discs were modified by an alkali treatment and a radio frequency (RF) plasma procedure (150 W and 13.56 MHz) in N(2), CO(2) or N(2)/O(2) (80/20%) atmospheres. After the alkali treatment, atomic force microscopy showed differences in the surface roughness of the samples. X-ray photoelectron microscopy indicated that the chemical composition of the surfaces changed after the different alkali and RF plasma treatments. The contact angles were also modified by approximately 5 degrees , making the original titanium surface more hydrophilic. Immersion in a supersaturated calcium phosphate solution was used to evaluate the bioactivity of the RF plasma-treated samples in vitro. Alkali-treated samples gave more homogeneous and thick coatings that those without alkali treatment. The use of RF plasma treatments enhanced the bioactivity of the samples, in particular for treatments performed in N(2) or N(2)/O(2) atmospheres. Energy-dispersive X-ray analysis indicated that coatings had Ca/P ratios between the values of octacalcium phosphate and hydroxyapatite. X-ray diffraction confirmed the presence of these two phases in most of the coatings. This study shows that an RF plasma treatment enhanced the bioactivity of titanium surfaces.
n class="Chemical">Titanium and its alloys, whenpan> treated inpan> alkali solutions, are able to form n class="Chemical">calcium phosphate coatings on their surface after immersion in supersaturated solutions. In this study, the surfaces of titanium alloy discs were modified by an alkali treatment and a radio frequency (RF) plasma procedure (150 W and 13.56 MHz) in N(2), CO(2) or N(2)/O(2) (80/20%) atmospheres. After the alkali treatment, atomic force microscopy showed differences in the surface roughness of the samples. X-ray photoelectron microscopy indicated that the chemical composition of the surfaces changed after the different alkali and RF plasma treatments. The contact angles were also modified by approximately 5 degrees , making the original titanium surface more hydrophilic. Immersion in a supersaturated calcium phosphate solution was used to evaluate the bioactivity of the RF plasma-treated samples in vitro. Alkali-treated samples gave more homogeneous and thick coatings that those without alkali treatment. The use of RF plasma treatments enhanced the bioactivity of the samples, in particular for treatments performed in N(2) or N(2)/O(2) atmospheres. Energy-dispersive X-ray analysis indicated that coatings had Ca/P ratios between the values of octacalcium phosphate and hydroxyapatite. X-ray diffraction confirmed the presence of these two phases in most of the coatings. This study shows that an RF plasma treatment enhanced the bioactivity of titanium surfaces.
Authors: Stefan Rupf; Ahmad Nour Idlibi; Fuad Al Marrawi; Matthias Hannig; Andreas Schubert; Lutz von Mueller; Wolfgang Spitzer; Henrik Holtmann; Antje Lehmann; Andre Rueppell; Axel Schindler Journal: PLoS One Date: 2011-10-10 Impact factor: 3.240