Enhancement of osteoblast proliferation in vitro by selective enrichment of demineralized freeze-dried bone allograft with specific growth factors

Decalcified freeze-dried bone allograft (DFDBA), believed to serve as a matrix for new bone growth and to contain various bone-inducing growth factors, is currently used to regenerate periodontal defects and to restore and maintain dental alveolar ridges. Growth factors within DFDBA are extracted during the demineralization process, thus rendering the allograft incapable of spontaneous osteogenesis; however, exogenous growth factor addition to DFDBA may enhance the osteogenic capacity of native osteoblasts. This study's purpose is to evaluate murine osteoblast proliferation in the presence of various exogenous soluble growth factors as measured by fluorescence units. Osteoblasts harvested from mouse pup calvaria were cultured with 2% residual calcium-DFDBA and supplemented by one of the following growth factors or combinations of these factors: transforming growth factor-beta (TGF-beta), insulin-like growth factor-I (IGF-I), platelet-derived growth factor (PDGF), fibroblast growth factors basic (bFGF), or vascular endothelial growth factors (VEGF). Osteoblast proliferation rates indicate that the in vitro supplementation of 2% residual calcium-DFDBA with the combination of IGF and TGF-beta, IGF and PDGF, and PDGF and TGF-beta significantly (P < or = .05) enhance murine osteoblast activity and proliferation at 7 days compared with the control containing no exogenous growth factors.