The Use of Platelet Rich Fibrin in Pulpal and Periodontal Regeneration

Purpose: Platelet rich fibrin (PRF) has been postulated to aid in regeneration. Therefore, the purpose of this study is to evaluate the inflammatory response of PRF in vitro, and analyze clinically and histologically the effectiveness of PRF on pulpal regeneration after reimplantation. Materials and Methods: The in vivo experiment included 18 patients (69 teeth). Teeth were extracted and apicoectomy performed. The tooth was reimplanted and splinted after PRF was condensed into the apex. Control teeth received the same treatment with the exception of the PRF. After 3-11 months, vitality was checked, teeth were extracted and analyzed histologically. For the in vitro, PRF was fabricated from two donors. A periodontal ligament (PDL) cell line was divided into four groups: A: PDL cells and PRF, B: PDL cells, PRF, and Lipopolysaccharide (LPS), C: PDL cells and LPS, and D: PDL cells only. After 24 h LPS was added to groups B and C. Supernatants were collected at 24, 48 and 72 h and an enzyme-linked immunosorbent assay was used to measure the concentration of IL-6. Results: PRF had no effect on diagnostic tests or histological outcome. Out of mouth time lead to more post-operative non-vital responses. For the cell cultures, PRF synergized with LPS inducing higher IL-6 release. Conclusions: PRF does not improve vitality responses in vivo and results in higher expression of IL-6 from PDLs