by Charles L. Penninger One of the most intriguing aspects of bone is its ability to grow, repair damage, adapt to mechanical loads, and maintain mineral homeostasis. It is generally accepted that bone adaptation occurs in response to the mechanical demands of our daily activities; moreover, strain and microdamage have been implicated as potential stimuli that regulate this sophisticated proces...

In the treatment of osteoporosis, the aim of the antiresorptive therapy is to restore bone density by decreasing bone remodeling. The process of bone remodeling plays a role in plasma calcium homeostasis and serves to modify bone architecture in order to meet changing mechanical needs, to maintain osteocyte viability, and to repair microdamage in bone matrix. Estrogen deficiency results in a nu...

Healing of the bone is different with the other part of the body. Fracture healing is actually a bone regeneration with no scar tissues, where as in wound healing, injured tissue is replaced by  connective tissue which became a scar, Traditionally fracture healing is divided in to 4 stages: 1) Stage of inflammation; 2) Stage of soft callus; 3) Stage of hard callus and 4) Stage of remodeling. In...

Bone remodeling is the restructuring process of existing bone, which is in constant resorption and formation. Under normal conditions, this balanced process allows the renewal of 5-10% of bone volume per year. At the microscopic level, bone remodeling is produced in basic multicellular units, where osteoclasts resorb a certain quantity of bone and osteoblasts form the osteoid matrix and mineral...

In older humans, bone elongation ceases, periosteal expansion continues, and bone remodeling remains a dominant metabolic process. An appropriate animal model of type I and type II osteoporosis would be a species with sealed growth plates and persistence of bone remodeling. The rat is commonly used as a primary model, but due to delayed epiphyseal closure with continuous modeling and lack of Ha...

Materials based on Mg2+-containing phosphates are gaining great relevance in the field of bone tissue repair via regenerative medicine methods. Magnesium ions, together with condensed phosphate play substantial roles process remodeling, affecting early stage regeneration through active participation osteosynthesis. In this paper we provide a comprehensive overview usage biomaterials magnesium a...

Seeman, Ego. Invited Review: Pathogenesis of osteoporosis. J Appl Physiol 95: 2142–2151, 2003; 10.1152/japplphysiol.00564.2003.—Patients with fragility fractures may have abnormalities in bone structural and material properties such as larger or smaller bone size, fewer and thinner trabeculae, thinned and porous cortices, and tissue mineral content that is either too high or too low. Bone model...