Effect of platelet rich fibrin associated or not with synthetic bone graft on bone healing of critical-size defects in calvaria of rats: a study histomorphometric, microtomograth and immunohistochemical

Abstract

Biomaterials have been widely used to promote bone regeneration in cases of bone loss, among them the platelet concentrates can be cited: platelet-rich plasma and plasma rich in fibrin. The purpose of this study is to evaluate the influence of Plasma rich in Fibrin (PRF) associated or not to a synthetic bone substitute (ReproBone) on bone healing in calvarial defects in rats. For that, 32 rats (Wistar) will be divided into 4 groups (n=8): C (control), PRF, REPRO and PRF-REPRO, and a critical-size defects (CSD) of 5 mm diameter will be created in the calvaria of each animal. In Group C, the defect will be filled only with blood clot; in the PRF Group, the defect will be filled with plasma rich in fibrin; in REPRO Group, the defect will be filled with a synthetic bone substitute ReproBone; in PRF-REPRO Group, the defect will be filled with synthetic bone substitute associated to PRF. After 30 days the animals will be sacrificed. To analyze the bone healing process created in the CSD, it will be evaluated: I) mineral bone density and bone microarchitecture through microtomography analysis; II) the number of newly formed bone and cellular profile of the bone healing process through histomorphometric analysis; III) expression of VEGF, PCNA, RUNX2, osteocalcin, osteopontin and BMP2 by immunohistochemical analysis. The differences will be evaluated using parametric or non-parametric statistical tests appropriate, considering the significance level of 5%. (AU)