Answer:
What is osseointegration? Osseointegration is the biological phenomenon whereby an inanimate material is incorporated into living bone. It is in essence an anchorage mechanism, which allows the attachment of prosthetic components to the skeleton. Achieving successful osseointegration depends on careful planning, meticulous surgical technique and skillful prosthetic management. The principle is utilized in dental and maxillofacial prostheses, replacement of diseased joints, and attachment of artificial limbs.
The biological process of osseointegration occurs as follows: following the initial placement of an implant, a thin (about 0.5 mm) layer of bone in the prepared site will become necrotic. This bone is replaced by the body as integration proceeds. Initially, an ingrowth of vascular loops will occur at a rate of 0.5 mm a day, followed by initial woven bone formation in the first 2 weeks following implant placement. Due to the inert nature of the implant, newly differentiating osteoblastic cells derived from the adjacent periosteum can synthesize a woven bone matrix that provides an initial bone contact to the implant. Then a remodeling phase is initiated in which osteoclastic cells form cutting cones that remove the established woven matrix at a rate of 40 micrometers a day. After this resorptive phase, an osteogenic front of lamellar bone differentiation occurs where newly differentiated osteoblasts lay down a haversian bone system in a process that is influenced by environmental factors such a micromovements of the interface, local vascular supply and systemic and local release of matrix-regulating growth factors. With time, the space between the implant and the bone will heal with new bone by reparative osteogenesis, or creeping substitution, resulting in clinical fixation of the implant. Over time, applied mechanical forces continue to stimulate the ongoing modeling of the bone necessary to maintain homeostasis.