Abstract
A number of materials have shown to be capable of inducing apatite formation in metasatble calcium- and phosphate-containing solutions known as simulated body fluids (SBFs). All these apatite inducers have a great number of acidic hydroxyl groups on their surfaces that include SiOH, TiOH and COOH. A hypothesis is thus proposed that a material could induce apatite formation when there are a large number of acidic OH groups present on its surface. These acidic OH groups could be introduced in the material via sol-gel processing routes and/or generated on the surface of a material as a result of its interaction with the solutions. The knowledge has been applied to develop a new process of growing an apatite film on titanium implants for enhancement of their fixation in bone.
