# Platelet-Rich Fibrin: A Viable Therapy for Endodontic-Periodantal Lesions? A Preliminary Assessment
###### Abstract  
Background and Objectives: The endodontic system and the periodontitis are closely interrelated and the infection of both leads to the appearance of endodontic-periodantal lesions. Along with the endodontic and periodontal classic treatment, in most cases, there is a need for regenerative periodontal therapy for the repair of the damaged tissue. One material that stimulates bone healing is represented by platelet-rich fibrin (PRF). The aim of this study was to determine if the inclusion of PRF in the treatment protocol of endodontic-periodantal lesions is effective. Materials and Methods: This review was conducted according to the PRISMA guidelines. Four databases, MEDLINE (through PubMed), Scopus, Web of Science, and Google Scholar, were used in order to find all significant articles on the topic. Relevant keywords were used in different combinations. Results: The inclusion criteria were met by six studies, published between 2014 and 2020 and they were selected for the review. The use of PRF for the regenerative therapy of endodontic-periodantal lesions showed favorable outcomes in all of the studies included, with significant reductions in the probing depths. Conclusion: While platelet-rich fibrin may be beneficial, further research is needed. platelet rich fibrin; prf; endodontic-periodantal lesion +
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Usually, the primary infection is the one to be treated first when the endodontic or periodontal lesion is present and the infection of the other structure has just started [1; 3; 4; 5], but when the second infection is chronic, both endodontic and periodontal treatments need to be conducted [6]. Frequently, the root canal treatment is performed first [5; 7], then the treatment of the residual periodontal pocket, which can be more anticipable after a successful endodontic treatment [3]. Scaling and root planning are included in the periodontal treatment, as well as regenerative procedures, which are essential to be taken into consideration for the repair of the damaged tissue (Figure 1) [8]. In a combined endodontic and periodontal lesion, the configuration of the bone defect and the degree of destruction of the periodontal attachment have a considerable influence on the long-term prognosis of the tooth [3]. In case of an advanced periodontal lesion, the success of the therapy revolves around the possibility of filling the defect using regenerative procedures [3]. For regenerative periodontal therapy, a material or a combination of materials that can stimulate healing in bone and soft tissue are used. One of the materials that possesses these properties is represented by platelet-rich fibrin (PRF) [9; 10]. It is an autogenous material that is formed of a fibrin matrix and has platelets, leukocytes, cytokines, circulating stem cells [11], macrophages [12], and growth factors [12; 13; 14] such as transforming growth factor-1 (TGF-\(\beta\)1), vascular endothelial growth factor (VEGF), platelet derived growth factors (PDGFs) and insulin-like growth factors (IGFs). In the literature several protocols aimed at improving the quality of the fibrin cloth which include variations in the spin time and speed. Included, in the PRF family are: leucocyte-platelet rich fibrin (L-PRF), titanium-platelet rich fibrin (T-PRF), advanced-PRF (A-PRF), and BioPRF. They can differ not only for the spin time and speed but also for the inclination and the surface treatment of the tubes used (Table 1). Time and speed are crucial determinants of the most effective autologous blood derivate. [PERSON] and coworkers [9] have stated that the fibrin scaffold and the concentration of growth factor differs between protocols; thus, the regenerative potential may differ. The inclination of the tubes is another factor that needs to be taken into consideration. [PERSON] et al. have reported that inclined spin might reduce the concentration of growth factor and the reduced production of the fibrin scaffold [10].