Histological Evaluation of the Effects of Growth Factors in a Fibrin Network on Bone Regeneration

Abstract

Objective: The aim of this study was to evaluate the effect of mineralized plasmatic matrix (MPM), comprising a combination of synthetic graft and platelet concentrates, on bone regeneration.

Methods: Critical size defects of 6-mm diameter were created on the tibias of 6 male sheep, with the animals subsequently assigned into 2 groups. Of the 5 bone defects generated per animal, 4 were randomly filled with MPM, beta-tricalcium phosphate graft (β-TCP), platelet-rich fibrin (PRF) + β-TCP, and autogenous graft. One defect was left empty as a control group. Animals were killed at 3 weeks (early healing group) and 6 weeks (late healing group). The specimens underwent histologic and histomorphometric analysis to evaluate new bone formation.

Results: In both healing periods, new bone formation from autogenous bone was observed significantly more often than from biomaterials or the empty defect. The degree of new bone formation for MPM was significantly higher than that of the control group at all healing periods. In addition, it was significantly higher in both healing periods than that of β-TCP albeit only in the late healing period than that of the PRF + β-TCP combination. In all biomaterial groups, residual graft ratios decreased from early to late healing periods.

Conclusion: The results indicated that MPM, representing growth factors in a fibrin network, increases new bone formation in surgically created defects in sheep tibia as confirmed by histologic assessment.