Ceramics-Silikáty 50, (3) 153 - 158 (2006)

The aim of this paper was to study the influence of precalcification process on the nucleation as well as growth of calciumphosphates crystals (Ca-P) on the surface of Ti alloy. Ti alloy was precalcified by the calcification solutions (SCS1-3) with different content of Ca²⁺ and (PO₄)³⁻ ions and compared with the non-precalcified sample. The results of Ca²⁺ and (PO₄)³⁻ analysis indicate that precalcification step accelerates the consumption of both Ca²⁺ and (PO₄)³⁻ ions from simulated body fluid (SBF) solution. The deposition of Ca-P phase was completed approximately 6 days earlier when compared it with the non-treated samples. Analytical measurements as well as the surface observation enable to find optimal calcification solution marked as SCS2 containing (mmol/dm³) 4.0 Na⁺, 5.0 Ca²⁺, 10.0 Cl⁻, 2.5 H₂PO₄⁻ and 1.5 HCO₃⁻. The influence of S/V ratio (surface area / volume of soaking media) changes on the nucleation and thickness of Ca-P layer formed in the SCS2 solution has been studied in the second part of this work. It was found out that 4 days immersion in SCS2 solution at S/V ratios at 0.1 and 0.5 cm⁻¹, respectively, is enough time for complete deposition by Ca-P phase on the alloy surface. The changes of the S/V ratio allow adjusting the thickness of Ca-P layer on the surface.