FTIR absorption-reflection study of biomimetic growth of phosphates on titanium implants

Titanium has been used for many medical applications; however, its joining to a living bone still is not satisfactorily good, challenging appropriate investigations. The aim of this work was to generate chemical modifications at its surface such that in vivo conditions, heterogeneous nucleation, and then growth of apatite from the body fluid could be easily induced and suc cessfully performed. For this purpose, on the titanium samples, the oxide s ublayers containing titanium, calcium and silicon (TCS) were deposited from a suitable solution using the sol-gel deep-coating procedure. Dried sample s were heated at 400 degreesC then cooled and thermostatically held in synt hetic body fluids (SBF, SBFIII) under physiological conditions to mimic the natural process of apatite formation. Changes in surface composition of TC S sublayers caused by the heating were studied with XPS. Infrared spectrosc opy and scanning electron microscopy monitored successive steps of apatite growth. It was found that in SEE at the precoated titanium surface, nucleat ion and growth of the apatite containing carbonate took place. In SBFIII, f or a higher concentration of calcium ions in comparison with SBF, a much-en hanced growth of the apatite free of carbonate was observed. TCS precoating s applied on stainless steel and Cr-Co-Mo alloy (Micromed) act also as bioa ctive interfaces with high ability to nucleation of biologically equivalent apatite. Biomimetic formation of this apatite on biologically inactive mat erials can be an important step in implant surgery. (C) 2000 Elsevier Scien ce B.V. All rights reserved.