Q. Define Osseointegration from patients, microscopic and biomechanical points of view.
a) From the view of the patient.
An implant fixture is osseointegrated if it provides a stable and apparently immobile support of a prosthesis under functional loads, without pain, inflammation or loosening over the lifetime of the patient.
b) From a view point of macro and microscopic biology and medicine.
Osseointegration of a fixture in bone is defined as the loose apposition of new and reformed bone in congruence with the fixture, including surface irregularities, so that at light microscopic level, there is no interpositioned connective or fibrous tissue and that a direct structural and functional connection is established, capable of carrying normal physiological loads without excessive deformation and without initiating rejecting mechanism.
c) From a macroscopic biomechanical point of view.
A fixture is osseointegrated if there is no progressive relative motion between the fixture and surrounding living bone and marrow under functional levels and types of loading for the entire life of the patient and exhibits deformation of the same order of magnitudes as when the same loads are applied directly to the bone.
d) From a microscopic biophysical point of view
Osseointegration implies that at light microscopic and electron microscopic levels, the identifiable components of tissue within a zone of a fixture surface are identified as normal bone marrow constituents which continuously grade into a normal bone structure surrounding the fixture: that mineralized tissue is found to be in contact with fixture surface over most of the surface within nanometers.