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In vitro evaluation of mechanical properties of platelet-rich fibrin membrane and scanning electron microscopic examination of its surface characteristics

Background: The aim of this study was to evaluate the mechanical properties of the platelet-rich fibrin (PRF) membrane and to compare these properties with that of commercially available collagen membranes used for guided tissue regeneration (GTR) procedures. Scanning electron microscopic (SEM) examination of PRF membrane was also performed to determine the cell distribution pattern within the different regions of the membrane. Materials and Methods: Modulus of elasticity and hardness of (i) PRF membrane (ii) bovine collagen membrane and (iii) fish collagen membrane were assessed by performing surface indentation test using T1 950 Triboindenter. The in vitro degradation tests were conducted by placing the (i) PRF membrane (ii) bovine collagen membrane and (iii) fish collagen membrane of equal sizes (10 mm Χ 5 mm) in 5 ml of pH 7.4 phosphate buffer solution on a shaker set at 40 rpm for 1-week. The degradation profiles were expressed as the accumulated weight losses of the membrane. SEM evaluation of the PRF membrane was done under both low and high magnification. Results: Young′s Modulus of elasticity was found to be 0.35 GPa for PRF membrane, 2.74 GPa for bovine collagen membrane and 1.92 GPa for fish collagen. The hardness was 10.67 MPa for PRF membrane, 110.7 MPa for bovine collagen membrane and 90.5 MPa for fish collagen membrane. PRF membrane degraded by about 36% of initial weight after a 1-week in vitro shaking test. Fish collagen membrane degraded by about 8% of initial weight, bovine collagen membrane degraded by about 3% of initial weight. Dense clusters of platelets formed due to extensive aggregation, and few leukocytes were observed in buffy coat area. Conclusions: The preliminary findings from the assessment of the mechanical properties of PRF membrane showed that it was lacking in several desired properties when compared to commercially available collagen membranes. Lack of rigidity and faster degradation may limit its application in GTR procedures.