Platelet-rich fibrin associated to bovine bone induces bone regeneration in model of critical-sized calvaria defect of rats submitted to Zoledronic Acid therapy: PRF induces bone healing.

Purpose: Reconstruction of bone defects prior to implant installation is a challenge, especially when the patient uses bisphosphonates. Given this difficulty, many studies investigate biomaterials that can improve the bone regeneration process. In this context, this study aimed to investigate the effect of platelet-rich fibrin (PRF) and Bio-Oss (BO) on bone regeneration of rats submitted to critical-sized calvaria defects and treated with ZA.

Methods: Thirty Wistar rats received a single dose of ZA (120 μg/kg) and after 7 days, were submitted to an 8 mm calvaria defect. The animals were divided into 5 groups (n = 6): ZA, BO, PRF or BO+PRF; animals from control group did not receive ZA. All animals were euthanized 12 weeks after surgical procedure and calvaria collected to histological, histomorphometric and micro-CT analyses.

Results: BO+PRF increased the number of osteoblasts (33 %) and osteoclasts (58 %), as well as blood vessels (70 %) and Type I collagen (52 %) (p < 0.05) compared to ZA group.

Conclusion: In summary, the association of BO+PRF improved bone healing of large bone defect in rats receiving ZA and this may be an interesting approach for the treatment to be tested in patients under anti-resorptive therapy.