Angiogenic and Regenerative Potential of Plasma-Based and Plasma-Free Platelet Concentrates Obtained via Different Fractionation and Activation Methods

Background: Platelet concentrates are widely used in regenerative dentistry and maxillofacial surgery; however, the lack of protocol standardization and selection criteria results in contradictory clinical outcomes. This study aimed to perform a comparative analysis of the biological activity of various platelet concentrates obtained via different fractionation and activation procedures under uniform in vitro experimental conditions. Methods: Rat adipose-derived stem cells (ADSCs) and human EA.hy926 endothelial cells were used to evaluate four platelet concentrate types via tube formation, wound healing (scratch), and cell proliferation assays. Results: Platelet concentrates obtained by the single-centrifugation protocol (L-PRP-1) exhibited maximal retained platelet potential, corresponding to a peak 5-fold increase in cell migration. Chemical activation of plasma-based concentrates (L-PRP, P-PRP) with calcium/thrombin was critically required to trigger angiogenesis and accelerate endothelial chemotaxis. Conversely, plasma-free platelet concentrate (PFPC) exhibited a unique capacity for spontaneous activation and clot formation without exogenous inducers, triggering rapid angiogenesis and sustaining ADSC proliferation. Conclusions: Within the framework of our in vitro model, activated plasma-based forms are biologically justified for accelerated soft tissue healing and socket preservation, whereas the complete removal of plasma proteins suggests the potential utility of PFPC as a biomimetic matrix-carrier for maxillofacial tissue engineering.