Desenvolvimento e aplicação clínica de concentrados sanguíneos de fibrina rica em plaquetas

Abstract

Platelet-rich blood concentrates originates from platelet collections in plasma solutions for surgical site use. The objective was to increase the release of growth factors and local cytokines for improved tissue repair. Platelet-rich fibrin (PRF) concentrate is considered an evolution in the generation of blood concentrates due to its additive-free production. Moreover, PRF ability to form a dense fibrin network permeated by cells and platelets, along with the high concentration of slow-release active molecules, makes it a promising tool for tissue repair improvement. The literature has proposed several PRF preparations based on different centrifugation times, relative centrifugal forces (RCF), and tubes of different materials. These parameter changes allowed the production of concentrates with specific characteristics according to their use goal. Thus, the general objective of this thesis was to compare protocols of PRF blood concentrates, collection tube types, and clinical applications to reduce postoperative inflammatory signs and symptoms in patients subjected to third molar extractions. Specific objective 1: To evaluate a new PRF protocol obtained through stepped variation of relative centrifugal force, produced in additive-free plastic blood collection tubes. Specific objective 2: To compare the performance of Vacuette® and S-PRF® tubes regarding collection efficiency, tensile strength, cellularity, and chemical composition of the tube in producing giant membranes using the progressive PRF protocol (PRO-PRF). Specific objective 3: To investigate, through a network meta-analysis, the effectiveness of blood concentrates in reducing pain perception, trismus, and edema after lower third molar extraction. After analyzing the obtained data, it was possible to conclude that: 1) The new progressive centrifugation protocol for platelet-rich fibrin (PRO-PRF), allows the production of giant PRF membranes with higher tensile strength and adequate cell distribution. Additionally, it enables the incorporation of biomaterials during production and clinical control of membrane thickness and size according to clinical need. Thus, providing sufficient parameters for a new generation of blood concentrates. 2) Vacuette® tubes are equivalent to S-PRF® tubes in collection performance, chemical composition, and produced membranes. Therefore, Vacuette® tubes represent a safe and cost-effective alternative for PRF membrane production. 3) Considering the low certainty of evidence, among the evaluated blood concentrates, A-PRF performed better and appeared to be effective in reducing postoperative pain after lower third molar extractions, and trismus decreased at the inflammatory peak.