Hydrogel and Injectable Platelet-Rich Fibrin: A Synergistic Approach to Osteogenesis.

Injectable platelet-rich fibrin (i-PRF) features a higher concentration of growth factor and lower viscosity compared with PRF, making it advantageous for periodontal regenerative therapy. However, its low mechanical property and high degradation rate cause its limited usage in bone augmentation. Hydrogel interacts with i-PRF, which is expected to replace bone graft considering its disadvantages. Through the synergistic effects of the materials, a sustained release of growth factor is achieved, promoting bone formation and maturation.Osteogenic markers, including alkaline phosphatase (ALP) activity and calcium deposition, were measured at intervals of 1, 7, 14, and 21 days using osteoblast-like cells. In vivo study using the extraction socket of Wistar rat applied with the same material was also done and measured at 21 and 42 days. The study included three groups: hydrogel i-PRF, bone graft (FDBA) i-PRF, and a control (blank hydrogel) group. Measurements utilized ALP staining and Alizarin red S assays for the in vitro study and bone dimension for the in vivo study.Hydrogel i-PRF significantly enhanced ALP activity on days 7 and 14 compared with the bone graft i-PRF and control groups ( ≤ 0.05). Similarly, calcium deposition was notably higher in the hydrogel i-PRF group on days 14 and 21. Hydrogel i-PRF also preserves the bone dimension of the rat's extraction socket compared with bone graft i-PRF. These findings highlight the superior bone regeneration capacity of the hydrogel when combined with i-PRF, attributed to enhanced osteoblast proliferation, differentiation, and mineralization mediated by PDGF and BMP bound to collagen fibrils.Hydrogel with i-PRF exhibits improved osteogenic capability compared with bone grafts, showing promise as an alternative material for periodontal regenerative applications.