Bone mineral and surface charge.

A triple association has been observed between a high negative surface charge, bone morphogenetic activity, and in vitro recalcificaiton in implants of demineralized bone matrix. Proplast fills with bony tissue when implanted in the body and shows the same triple association. The higher the negative surface charge, the greater is the mass of new bone induced and the higher degree of mineralization when placed in a calcifying solution in vitro. Further investigations are necessary to determine whether in implants of demineralized bone, a high negative surface charge may cause the formation of discrete calcium deposits or whether it triggers the invading primitive cells to differnetiate and produce bone, or both.