ABSTRACT
The communication of an implant with the host system takes place initially via the surface. This initial, direct contact between the living tissues in the body and the surface is a major factor that determines the rejection or acceptance of a foreign device. In general terms, the ideal biomaterial should have adequate mechanical (and other) properties while the surface should have good biocompatibility, i.e., a material must possess not only suitable mechanical properties in order to function properly in a bioenvironment, but should also not be harmful for the host tissue and if possible, should not induce any inflammatory response. For instance, a material for hip joint has to be able to stand high stress and at the same time, cells should proliferate on its surface. In other cases — for example, for catheters — the requirements are opposite; the material is considered to be compatible if it is flexible enough and prohibits cell growth. However, it is rare that a biomaterial with good bulk properties also possesses the surface characteristics suitable for clinical application, and very few surfaces are truly biocompatible. This has been discussed in a review by Chu et al.
