Comparison of Fibrin Characteristics and Cellular Contents of Injectable Platelet-rich Fibrin Enriched Bone Block ("Sticky Bone") Prepared Using Novel and Traditional Protocols - An <i>In vitro</i> Study.

Abstract

<h4>Background</h4>Injectable platelet-rich fibrin (i-PRF) can be combined with bone graft materials to enhance its healing potential. Studies on improving the fibrin density and degradation properties of i-PRF-enriched bone grafts are lacking.<h4>Aims and objectives</h4>The aims and objectives of the study are to compare the fibrin porosity (density), solidification time, degradation properties, and cell counts of (i-PRF) bone blocks prepared using novel and traditional protocols.<h4>Materials and methods</h4>Venous blood (10 ml) was collected from six healthy volunteers to prepare the novel i-PRF in silica-coated plastic tubes (2000 g for 3 min) and traditional i-PRF in non-coated plain plastic tubes (700 g for 8 min). The i-PRF was mixed with xenograft to prepare the novel (NBB) or traditional bone blocks (TBB). The total solidification time and degradation properties of the bone blocks were analyzed. The density of the fibrin network in the bone blocks was compared using scanning electron microscopy images. The total and differential cell counts in the i-PRF were compared to those in whole blood.<h4>Results</h4>The NBBs had higher fibrin density (10-fold) and solidified faster (3-fold) than the TBBs (<i>P</i> < 0.001). The NBBs were more stable and resistant to degradation (>10 days), whereas the TBBs degraded within 4-6 days (average 4.67 days). The cell counts of both platelets and leukocytes in the novel and traditional i-PRF were significantly higher than the whole blood control (<i>P</i> < 0.001).<h4>Conclusion</h4>The novel protocol significantly enhanced the fibrin density, stability, and cell counts of the i-PRF bone blocks and shortened the solidification time.