Implant fixation by bone ingrowth

The term osseointegration referred originally to an intimate contact of bon e tissue with the surface of a titanium implant; the term bone ingrowth ref ers to bone formation within an irregular (beads, wire mesh, casting voids, cut grooves) surface of an implant. The section dealing with the historica l background describes the development of macroporous, microporous, and tex tured surfaces with an emphasis on the evolution of porous and textured met al surfaces. The principal requirements for osseointegration and bone ingro wth are systematically reviewed as follows: i) the physiology of osseointeg ration and bone ingrowth, including biomaterial biocompatibility with respe ct to cellular and matrix response at the interface; ii) the implant surfac e geometry characteristics; iii) implant micromotion and fixation modes; an d iv) the implant-bone interface distances. Based on current methods of bon e ingrowth assessment, this article comparatively reviews and discusses the results of experimental studies with the objective of determining local an d systemic factors that enhance bone ingrowth fixation.