Lamellar compaction and remodeling (6 to 18 weeks)
A remodeling phase is initiated in which hematopoietic-derived osteoclastic cells form cutting cones will remove the established woven matrix (at a rate 40 μm day). An osteogenic front of lamellar bone differentiation occurs where newly differentiated osteoblasts lay down a mature haversian bone system. This process is influenced by environmental factors such as micro movements of the interface, local vascular supply, and systemic and local release of matrix regulating growth factors. In time, the space between the implant and the bone heals with new bone by a reparative osteogenesis, referred to as creeping substitution, resulting in the clinical fixation of the implant.
To maintain sufficiently strong bone implant fixation for post-operative load bearing, it is important to preserve adequate primary implant stabilization and prevent overloading of the newly generated bone that offers secondary support during this interfacial remodeling. This seems to be the only explanation for the fact that maxillary implants are generally granted a much longer unloaded healing phase.