Platelet-rich fibrin for repair of oral soft tissue defects / 中国组织工程研究

ABSTRACT

BACKGROUND:Insufficient oral soft tissues in the implant zone may have a negative effect on the wound healing and the aesthetic restoration in the late stage. Platelet-rich fibrin can promote the wound healing of soft tissue defects. But there is stil a lack of in-depth studies on the promotion of oral soft tissue defects in animal experiments. OBJECTIVE: To compare the repairing effects of platelet-rich fibrin and colagen membrane on soft tissue defects of the hard palate in New Zealand rabbits. METHODS:Fifty-four New Zealand rabbits were randomly divided into three groups (n=14 per group) platelet-rich fibrin group, colagen membrane group and blank control group. A 5 mm-diameter circular ful-thickness soft tissue defect was made in the front of the hard palate, 2 mm distant to the rear maxilary incisors and mucosal edge of the bilateral hard palates. Autologous platelet-rich fibrin membrane or colagen membrane were implanted into the defect in the platelet-rich fibrin group and colagen membrane group, respectively. No treatment was given in the blank control group. General observation of the wound and wound healing analysis were performed at days 3, 7, 14, 21, 28, 56 post operation. Hematoxylin-eosin staining, CD31 immunohistochemical staining and Masson staining were used to observe inflammatory reaction, angiogenesis and colagen formation in the surgical site. RESULTS AND CONCLUSION:The wound healing rate was fastest in the platelet-rich fibrin group, and no obvious scar formed. At 3 days post operation, there was no difference in the wound healing rates among the three groups; at 7 days, the wound healing rate in the platelet-rich fibrin group was significantly higher than that in the colagen membrane group and blank control group (P < 0.05). At 3 and 7 days after operation, the inflammatory reaction in the platelet-rich fibrin group was less than that in the colagen membrane and blank control groups (P < 0.05); at 14, 21, 28 and 56 days, there was no significant difference between the three groups. At 7, 14, 21 days after operation, the average absorbance value of CD31 in the platelet-rich fibrin group was significantly higher than that in the colagen membrane and blank control groups (P < 0.05). The average absorbance value of colagen formation in the platelet-rich fibrin group was significantly higher than that in the colagen membrane and blank control groups at 7 days after operation (P < 0.05), significantly higher than that in the blank control group at 14 days (P < 0.05), but lower than that in the colagen membrane and blank control groups at 21, 28 and 56 days after operation (P < 0.05). These findings show that platelet-rich fibrin can reduce inflammatory reactions in the process of wound healing, accelerate the angiogenesis, regulate the metabolism of colagen, reduce the formation of scar and improve the quality of wound healing, thereby promoting the repair of oral soft tissue defects.