Assessment Effectiveness of Platelet Rich Plasma in Wound Healing After Surgical Removal of Mandibular Third Molars: A Clinical Study

The study is designed as a prospective randomized comparative clinical study. The sample population was composed of fifty consecutive patients who needed surgical extraction of lower third molar under local anesthesia. The study included 37 male and 13 female with age ranging from 20 to 40 years. All Patients were categorized into GROUP A (wound in which PRP is placed) and GROUP B (socket without PRP). The patients were allocated randomly to each group equally by single-blind technique, irrespective of age and sex.

Ethical approval was obtained from the Institutional Ethics Committee prior to the beginning of the study. The signed consent form obtained from all the patients after explaining the risks and benefits of the surgical procedure. The group A (test group) received topical application of PRP, whereas the group B (control group) was left to heal without PRP.

Clinical assessment:

Postoperative pain was assessed using a 10-point visual analog scale (VAS) with a score of 0 equals "no pain" and 10 equals "very severe pain" Facial swelling was assessed by modification of Schultze-Mosgau et al method, and this involved measuring the length from the tragus to the oral commissure and tragus to the pogonion. The arithmetic sum of the two measurements was considered as facial swelling at the time point. The maximum distance between the maxillary central incisors and the mandibular central incisors was taken as mouth opening. The difference between postoperative and preoperative mouth opening value was considered as trismus. Assessment of soft tissue healing was based on the criteria given by Landry et al. and Gonshor et al. Third molar sockets were assessed radiographically for bone healing by modification of Kelley's method as described by Olufemi et al. The percentage of facial swelling and mouth opening was estimated using the method described by Ogundipe et al.

Protocol for preparation of PRP gel Under all aseptic conditions, PRP was processed by means of a modification of the method of Sonnleitner et al. Before surgery, 10 mL of venous blood was collected from the antecubital fossa of the patient's forearm and stored into sterile tubes containing anticoagulant (0.5 mL citrate phosphate dextrose) from each patient of group A in the experimental group using routine venipuncture procedure. The tube was thoroughly agitated to ensure mixing of anticoagulant with the venous blood. The whole blood is then centrifuged at 1,200 rpm for ten minutes. The supernatant layer obtained was platelet poor plasma (PPP) and Buffy coat (BC) and RBCs (red blood cells) at the bottom part. PPP, BC and upper 1-2 mm of RBC (red blood cell) layer was collected in a new sterile tube and centrifuged again at 1,000 rpm for 10 min. The upper half of the supernatant is removed and the lower half is mixed carefully to get PRP. The platelet concentration of the PRP was noted.