CHARACTERIZATION OF MICROBLASTED AND REACTIVE ION ETCHED SURFACES ON THE COMMERCIALLY PURE METALS NIOBIUM, TANTALUM AND TITANIUM

In surface-roughened metallic implant materials, the topography, chemi stry and energy of the surfaces play an important role for the cell an d tissue attachment. The highly reactive commercially pure metals niob ium, tantalum and titanium were analysed after microblasting (with Al2 O3 powder and consecutive shot-peening with ZrSiO2), and after additio nal reactive ion etching (RIE, with CF4). Scanning electron microscopy in combination with energy-dispersive X-ray analysis and surface roug hness measurements showed, for all microblasted surfaces, a heterogene ous roughening (R-a about 0.7 mu m), and a contamination with blasting particles. RIE resulted in a further roughening (R-a about 1.1 mu m), and a total cleaning from contaminations, except for traces of alumin ium. Determination of surface energy by dynamic contact angle measurem ents showed an increase in surface energy after microblasting, which f urther increased after RIE, most pronounced for commercially pure niob ium. In conjunction with superior electrochemical properties, this mak es niobium and tantalum promising candidates for implant purposes, at least equal to the generally used titanium.