Bone morphogenetic protein（BMP）-2 has been shown as a key molecule in bone regeneration. It can induce the undifferentiated mesenchyma stem cell to differentiate to osteoblast cell. To develop a stable and sustained releasing system of BMP-2 is the focus, not only for treatment, but also for reducing the complication. This paper was to summarize the necessity, the materials, the property and the research tendency of the release system.
