[Innovative methods and developments in oral care. L-PRF: from evidence to clinical use]. / Serie: Innovatieve technieken en ontwikkelingen in de mondzorg. L-PRF: van evidence naar toepassingen in de praktijk.

Leukocyte- and platelet-rich fibrin (L-PRF) is a fully autologous biomaterial made from venous blood drawn from the patient. Due to its regenerative potency, antibacterial capacity, and analgesic activity, L-PRF can be used during surgical procedures as a sole biomaterial or as a bioactive additive along with other natural and synthetic biomaterials. There is sufficient scientific evidence available for applying L-PRF for various indications. The preparation protocol of L-PRF is simple, inexpensive and not time-consuming, making it possible to implement it in the daily practice. The type of centrifuge and blood collection tubes used, the settings of the centrifuge (rotation time and force) as well as the time between the different steps in the protocol have an influence on the biological and mechanical properties of L-PRF.

Impact of local and systemic antimicrobials on leukocyte- and platelet rich fibrin: an in vitro study.

The aim of this study was to evaluate the effect of local and systemic administration of antimicrobials to leukocyte- and platelet-rich fibrin (L-PRF). For part A, 16 tubes of venous blood were collected from each of eight systemically healthy subjects. Prior to blood centrifugation, 12 of the 16 tubes were injected with 0.125 ml, 0.25 ml or 0.50 ml metronidazole solution. One set of L-PRF membranes was used to assess the release of vascular endothelial growth factor AB, platelet-derived growth factor, transforming growth factor beta 1, and bone morphogenetic protein 2 at indicated time points. The metronidazole release over time by L-PRF membranes was also evaluated. The remaining L-PRF membranes were placed on the surface of agar plates inoculated with three different periodontal pathogens to determine their antibacterial activity. For part B, another six subjects were enrolled with three subjects taking 2 g amoxicillin and three subjects 500 mg metronidazole as prophylaxis prior to a periodontal treatment. Before and 2 h after consuming one of the prescribed antimicrobials, three tubes of blood were collected for preparing L-PRF membranes. These membranes were used to measure the antibacterial activity against periodontal pathogens. No statistically significant difference could be found in the release of growth factors between L-PRF membranes with and without incorporation of metronidazole solution. The release of metronidazole could be detected up to day 3, however with the highest concentration during the first 4 h. This concentration was dose dependent. The antibacterial capacity of L-PRF membranes increased significantly for both the systemic intake, and after the addition of metronidazole solution to the blood tubes before centrifugation, the latter again dose dependent. The antibacterial capacity of L-PRF against the periodontal pathogens tested can significantly be enhanced by the addition of antimicrobials, without disadvantage for the release of growth factors.