Behavior in simulated body fluid of calcium phosphate coatings obtained bylaser ablation

Three types of calcium phosphate coatings onto titanium alloy substrates, d eposited by the laser ablation technique, were immersed in a simulated body fluid in order to determine their behavior in conditions similar to the hu man blood plasma. Neither the hydroxyapatite coating nor the amorphous calc ium phosphate coating do dissolve and the alpha-tricalcium phosphate phase of the coating of beta-tricalcium phosphate with minor alpha phase slightly dissolves. Precipitation of an apatitic phase is favored onto the hydroxya patite coating and onto the coating of beta-tricalcium phosphate with minor alpha phase. Onto the titanium alloy substrate reference there is also pre cipitation but at larger induction times. However, onto the amorphous calci um phosphate coating no precipitate is formed. (C) 2000 Elsevier Science Lt d. All rights reserved.