Effect of Platelet-rich Fibrin on Soft-tissue and Hard-tissue Healing following Surgical Extraction of Mandibular Third Molar: A Prospective Interventional Study

Introduction: Surgical removal of mandibular third molars is one of the most frequent clinical tasks conducted by dental surgeons. This surgery is associated with the possibility of delayed and complicated soft-tissue and hard-tissue healing. Local incorporation of bioactive materials (such as growth factors and blood products) has been attempted to promote faster and better healing. Platelet-rich Fibrin (PRF) is the latest development among blood-derived products and is widely used to enhance hard and soft-tissue healing. Aim: To estimate the effect of PRF on soft-tissue and hardtissue healing following the surgical extraction of mandibular third molars. Materials and Methods: This prospective interventional study was carried out in the Department of Oral and Maxillofacial Surgery at Guru Nanak Institute of Dental Science and Research, Kolkata, West Bengal, India. The study was conducted between May 2022 and January 2024. Patients who required extraction of impacted mandibular third molars were divided into two groups (group I and group II) by alternate selection methods. PRF was placed in the empty sockets of group I patients following the surgical extraction of the third molar, while the sockets of group II patients were allowed to heal without PRF. Soft-tissue healing evaluation was performed using the parameters of the healing index on the 3rd, 7th, 14th, and 28th post-extraction days by two blind observers. Hard-tissue healing was evaluated using the Cone Beam Computed Tomography (CBCT) findings on the 1st month and 3rd month postoperatively. Changes in empty socket volume, Bone Density Units (BDU) of the new bone, and the type of new bone were analysed. Statistical analysis was carried out using IBM Statistical Package for Social Sciences (SPSS) Statistics for Windows, version 26.0 (Armonk, NY: IBM Corp). A p-value of <0.05 was considered significant. Results: Twenty-six patients were included in the final analysis. They were equally divided into the interventional group (group I, with PRF) and the control group (group II, without PRF). The demographic data and difficulty index of group I were similar to those of group II. The corrected Chi-square test of independence was performed to compare soft-tissue healing. A highly significant association was found on the 3rd postoperative day (p-value=0.03), 14th postoperative day (p-value=0.013), and 28th postoperative day (p-value=0.002), indicating that group I consistently demonstrated improved healing compared to group II. The volume of the empty socket of the extracted third molar was measured using CBCT on the 1st and 3rd postoperative months. In both groups, the volume reduced significantly, but the reduction was more pronounced in group I than in group II (p-value <0.0001). The quality of bone formation (measured by BDUs) was significantly better in group I than in group II (p-value=0.043). However, the type of bone formation was similar for both groups. Conclusion: PRF appears to be beneficial and effective in promoting postoperative soft-tissue and hard-tissue healing following the surgical extraction of mandibular third molars.