الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Certain orthopedic devices can be used as permenant implants for hard tissue replacement. Materials requirements of these devices include adequate mechanical strength, resistance to corrosion, and biocompatability. Titanium and its alloys are the most biomaterials fullfill all these requirements. However, some technichal problems associated with using titanium as an implant material are present. The bioinert character of its protective surface oxide layer does not readily form a strong interface with surrounding tissue. Additionally, the relatively high stiffness of titanium, as compared to surrounding bone, can lead to stress shielding and subsequent implant loosening, Spoerke, et al, 2005 236.
Coating of titanium implant surface with calcium phosphate ceramic material was suggested to have better interface integrity Wang et al, 1993 265. It was evident that hydroxyapatite coated implants have been enhanced mechanically and clinically via increased interfacial strength and rapid osseointegration compared to uncoated ones. Furthermore, creation of nano-porous titanium implant surface promoted bone growth, regeneration and improved implant interfacial strength, Bayoumi et al,2006 29 .
Protein adsorption is the primary factor controlling cell adherence and their subsequent cell activation which include spreading and migration on the substrate, Pilliar, 1987 206 . Cellular adhesion takes place via recognition and interaction with specific functional domain biomolecules in protein structure adsorbed on biomaterial surface, Bizios , 1994 36 . i.e. cellular response to foreign material is mediated by protein adsorption at the implant-bone interface for better biointegration, Homan and Cooper 1991 119