Assessment of efficacy of platelet rich plasma application in regeneration of the facial nerve in rabbits

Abstract

Background/Aim.The injuries of the facial nerve leading to paralysis of the mimic facial musculature, which is conditioned by functional disorders accompanied by deformity of varying degrees depending on the intensity and location of the injury. Surgical treatment is a method of choice to treat an injured nerve. Injuries in the parotid lodge area are based on direct neurosuture in combination with platelet rich plasma.Methods. The experimental study was carried out on 48 large chinchillas (Oryctolagus cuniculus) male rabbits, about the same weight (2500-3000 gr) of the age between 3 and 4 months in two surgical stages, in two different periods six and ten weeks after the first surgical procedure. The animals were divided into four groups (suture, suture, and fibrin glue, platelet rich plasma and suture; sutures, fibrin glue, and platelet rich plasma), based on the type of surgical treatment, each group had two subgroups based on the duration of the experiment (six and ten weeks). A part of the dissected nerve in the length of 5 mm was subjected to histologic verification where the number of axons and Schwan cells was determined on the basis of the histological sample of the tissue of the observed nerve and expressed numerically. The extent of the presence of connective tissue and the degree of neovascularisation is shown by the description of histological samples by grades 1-4 (1 no blood vessels, 2 individual blood vessels, 3 blood vessels).Results. Our results show that all parameters of regeneration of damaged nerve show significantly higher regeneration efficiency after six and ten weeks of intervention in groups treated with platelet-rich plasma therapy with or without the use of fibrin glue. Conclusion. The use of platelet-rich plasma and the stimulating effect of activated growth factors results in the regeneration of the facial nerve in the sense of replication of the Schwann cells and the number of axons, with a high degree of neovascularization and minimal proliferation of connective tissue which histologically corresponds to a healthy nerve.