Comparative Histopathological Evaluation of Platelet-Rich Plasma Injection and Autologous Blood Injection to Temporomandibular Joint: A Pilot Experimental Study

Chronic recurrent TMJ dislocation adversely affects patients’ lives. Various surgical and non-surgical methods have been used for treating recurrent TMJ dislocation. Some non-surgical methods include physiotherapy, occlusal splint, and avoidance of activities causing large-mouth- opening, and autologous blood or Platelet- Rich Plasma- injection to the Temporomandibular Joint (TMJ). This experimental study aimed to compare the histopathological evaluation of Platelet-Rich Plasma (PRP) injection and autologous blood (AB) injection to the Temporomandibular Joint. This experimental study was conducted in an animal lab affiliated to the Gazi University of Medical Sciences, Ankara, Turkey, in 2016. Bilateral TMJs from 12 young New Zealand White rabbits were assessed in the study. The animals were divided into two experimental groups with equal numbers (n = 6) including PRP and AB injection groups. For the experimental groups, 1 mL was injected into the upper joint space and 0.5 mL to the pericapsular tissue. The injections were administered unilaterally. Moreover, 1 mL of isotonic saline was injected into the contralateral sides of TMJ upper joint space and 0.5 mL into the pericapsular tissue to serve as controls for both groups. One month after the experimentation, the animals were sacrificed, and histological analyses were performed for fibrosis and tissue reactions. Collagen fibers and adipose tissue production in the retrodiscal ligament were more in the PRP group than in the AB group. According to the fibrosis classification, similar fibrotic changes were observed in the AB and PRP-injected tissue samples compared to controls. No cartilage degeneration was seen in either of the two groups. Considering the limitations of this study, PRP injection may be an alternative to AB injection for treating chronic mandibular dislocation. Clinicians could safely use the PRP injection technique to increase the success rate of the treatment.