Comparison of the Regenerative Effects of Platelet-Rich Fibrin and Plasma Rich in Growth Factors on Injured Peripheral Nerve: An Experimental Study

Abstract

Purpose: The aim of this study was to investigate the effects of platelet-rich fibrin (PRF) and plasma rich in growth factors (PRGF) on peripheral nerve injury in the early period of healing. Material and Methods: Thirty Wistar albino rats were used in this study. Rats were divided into control (C), damaged (D), PRF, and PRGF groups. The left sciatic nerves of each group were identified as group C. Crush-type injury was performed on the right sciatic nerves of the D, PRF, and PRGF groups. In the PRF and PRGF groups, blood 2 mL was obtained to prepare the PRF and PRGF and the biomaterials were applied to the injured nerve area. After 8 weeks, functional, electrophysiologic, and stereological evaluations were performed. Results: For the electrophysiologic evaluation, the latency and amplitude values in the D, PRF, and PRGF groups were significantly lower than those in the C group (P>.05). According to the sciatic functional index result, there were significant differences between groups D and PRF and between groups D and PRGF (P=.000). For the stereological evaluations, although no significant difference was observed between the PRGF and C groups (P>.05), a significant difference was observed among the D, PRF, and PRGF groups for myelinated axon number. There were significant differences between groups D and PRF and between groups D and PRGF for axon area (P=.021 and .001, respectively). No significant difference was observed among the D, PRF, and PRGF groups for myelin sheath thickness and ratio of axon area to myelin sheath thickness (P>.05). Conclusions: The results of this study suggest that PRGF increases nerve regeneration in the early period of healing and that the limited early action of PRF should be re-evaluated in the late period. (C) 2018 American Association of Oral and Maxillofacial Surgeons