Sustainability and Release Pattern of Growth Factors from Bone Grafts Prepared with Platelet-Rich Fibrin.

BACKGROUND:Platelet-rich fibrin (PRF) is used to prepare "sticky bone" by combining it with bone graft material. The present study investigated the ability of different bone grafts to absorb growth factors from the PRF and release them over time. MATERIALS AND METHODS:Human blood was collected from 10 healthy volunteers for liquid PRF preparation. Bovine bone, allograft (mineralized and demineralized), and synthetic bone were each mixed with the PRF to prepare a sticky bone. All sticky bone samples were incubated for up to 4 days. The absorption and release pattern kinetics of two selective growth factors within the PRF-platelet-derived growth factor (PDGF) and bone morphogenetic protein-2 (BMP-2)-were quantified with immunofluorescence staining and enzyme-linked immunoassay (ELISA) testing. RESULTS:All bone graft materials adsorbed the examined growth factors from the PRF. β-TCP showed the highest adsorption levels, followed by the xenograft, and the allografts showed the lowest adsorption levels. Furthermore, PDGF showed a fast-release pattern from the grafts, whereas BMP-2 was released at a later stage. Similar to the adsorption pattern, the β-TCP and xenograft were better able to sustain the release of the PRF growth factors from the graft than the allografts. CONCLUSIONS:The adsorption of PDGF and BMP-2 differ between graft materials, with superior results for β-TCP, followed by xenograft, then allograft materials.