Osseointegration is defined "as a direct structural and functional connection between ordered, living bone and the surface of a load-carrying implant". It is now said that an implant is regarded as osseointegrated when there is no progressive relative movement between the implant and the bone with which it has direct contact. In practice, this means that in osseointegration there is an anchorage mechanism whereby nonvital components can be reliably and predictably incorporated into living bone and that this anchorage can persist under all normal conditions of loading. It is a direct bone anchorage to an implant body, which can provide a foundation to support prosthesis; it has the ability to transmit occlusal forces directly to bone. Success rate of 80-100 per cent have been reported after a fifteen-year study of osseointegrated implants in the treatment of edentulous jaws.