Histological examination of the effects of platelet-RİCH fibrin and alloplastic graft applications on the healing of experimental bone defects created in the rabbit skull

The aim of this study is to histological evaluate the effects of the use of synthetic bone grafts and platelet rich fibrin based matrices in combination with the graft or as a membrane on the healing of bone defects created in the rabbit skull. Twelve New Zeland female rabbits were included in the study. Four bicortical experimental defects of eight milimeters in diameter were created in the parietal bone of each animal. Bone graft mixture based on injectable-platelet rich fibrin (i-PRF) and Beta Tricalcium Phospate (β-TCP) in the first defect (Group 1), enhanced platelet rich fibrin (a-PRF) in the second defect (Group 2), β-TCP based bone in third defect graft (Group 3) was applied; the fourth defect was left blank (control group). The subjects were randomly divided into two groups and sacrificed at the fourth and eight weeks. Sections taken from the defect areas were evaluted histopathologically and histomorphometrically. According to the intergroup analysis performed at the fourth week, the mean values of osteoblastic activation and new bone matrix synthesis in Group 1 were found to be statistically significantly higher than in Group 4 (p < 0.05). In the fourth week, the mean value of osteocyte activation in Group 1 was observed to be significantly higher than in Group 3 (p < 0.05). In the eighth week, the degree of inflammation in Group 3 was found to be significantly higher than in Group 4 (p < 0.05). In our study, compared to the use of only β-TCP grafts in the treatment of bone defects; ıt was determined that the combined use of i-PRF provided more and faster new bone formation, while the use of a-PRF resulted in a more dense bone tissue with mature component. As a result of our findings, it is thought that more succesful results can be obtained with use of PRF based biomaterials alone or in combination with graft in regenerative periodontal treatments. Further studies are needed to evaluate the effects of β-TCP, i-PRF and a-PRF on bone regeneration using immunohistochemical and computed tomographic methods. Keywords: Bone Mineralization, Growth Factors, Osseointegration, Regeneration, Wound Healing