Review Article

The Current and Future Therapies of Bone Regeneration to Repair Bone Defects

Figure 1

The schematic outlines of the bone remodeling cycle and the balance of bone resorption and bone formation. (a) In bone tissue, the osteoblasts are involved in new bone formation, while osteoclasts play a major role in bone resorption. The first step in the bone remodeling cycle is the resorption of existing bone by osteoclasts, followed by formation of the cement line in resorption lacunae and osteoblasts. Each cell type seems to be regulated by a variety of hormones and by local factors. (b) If the balance between bone formation and resorption is lost by the uncontrolled production of regulators, bone structure would be strikingly damaged, and the subject would be susceptible to osteoporosis and osteopetrosis.
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