Effectiveness of Platelet Rich Plasma in Wound Healing
Condition: Impacted Third Molar Tooth
MeSH terms: Tooth, Impacted
Study type: Interventional
Phase: Early Phase 1

Summary: 
      Purpose: This prospective randomized comparative clinical study was conducted to assess the
      effect of platelet-rich plasma (PRP) gel on soft tissue healing and bone regeneration
      potential on lower third molar extraction sockets.

      Methods: For the study, 50 Patients (37 male, 13 female) requiring surgical removal of a
      lower impacted third molar and who fulfilled the inclusion criteria were recruited. The
      patients were categorized into two groups, Group A and Group B. For each group 25 patients
      were randomly allocated. The predictor variable in Group A was the application of PRP Gel
      whereas in Group B had no PRP. Postoperative pain, swelling, trismus, soft tissue healing and
      osseous regeneration was assessed using standard methods. These outcome variables were
      assessed on 1, 3-, 5-, 7-, and 14-postoperative day. Patients were recalled at the 4th, 10th,
      and 16th postoperative week for assessment of bone healing. The data were recorded and
      tabulated.
    

Detailed description: 
      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.

      PRP gel was prepared by adding Five drops of the mixture of 10 % CaCl2 and 1000 U bovine
      thrombin to 2mL (milliliter) PRP just before its use in extraction socket.

      Surgical procedure The surgical extraction procedure was the same in all patients and carried
      out by the same operator. After achieving Local anesthesia using 2% lignocaine hydrochloride
      with 1:100,000 epinephrine, standard Terrence Ward's incision was placed to raise a full
      thickness mucoperiosteal flap. Distobuccal bone was carefully exposed and bone surrounding
      the buccal aspect of impacted tooth was performed using surgical bur under copious irrigation
      with 0.9% saline. The tooth was elevated using Coupland elevator and if required situations
      tooth was sectioned with surgical bur to facilitate its removal. The socket was checked for
      any tooth or bony debris. The bony margins smoothened using a file and irrigated with normal
      saline. Subsequently, PRP gel was placed into the extraction sockets of patients in the group
      A and wound closure was done using simple interrupted 3.0 black silk sutures. In group B the
      wound is closed without application of PRP gel. Patients were advised regular post extraction
      and prescribed 500 mg of paracetamol postoperatively (1 tablet every 6 h for 2 days).

      All patients were also advised to not consume any medications but those advised and not to
      get medical help somewhere else for postoperative discomfort or pain without prior
      information to the operator. The patients were reviewed postoperatively on 1-, 3-, 5-, 7-,
      and 14-day to record pain, mouth opening, Soft tissue and bony healing index. Patients were
      recalled at the 4th, 10th, and 16th postoperative week for assessment of bone healing.

      Statistical analysis:

      The data were analyzed using SPSS (Statistical Package for the Social Sciences) version 21.
      Descriptive statistics such as mean, SD (standard deviation ) and percentage were used.
      Normality of data was tested by using Kolmogorov and Smirnov method. Unpaired t-test was used
      to compare between groups with normally data and Mann-Whitney test for non-normally data. For
      categorical variables, Chi-square test was employed. A p-value less than 0.05 were considered
      as significant.
    

Intervention name(s): Local anesthesia; surgical extraction of impacted third molar; Preparation of PRP gel; Placing platelet Rich plasma and suturing; Suturing; Postoperative medication
Intervention type(s): Drug; Procedure; Biological; Procedure; Procedure; Drug
Intervention description(s): The surgical extraction under local anesthesia (2% Lignocaine and 1:100000 Adrenaline) procedure was the same in all patients.; After achieving Local anesthesia using 2% lignocaine hydrochloride with 1:100,000 epinephrine, standard Terrence Ward's incision was placed to raise a full thickness mucoperiosteal flap. Disto-buccal bone was carefully exposed and bone surrounding the buccal aspect of impacted tooth was performed using surgical bur under copious irrigation with 0.9% saline. Tooth was elevated using Coupland elevator and if required situations tooth was sectioned with surgical bur to facilitate its removal. The socket was checked for any tooth or bony debris. The bony margins smoothened using a file and irrigated with 0.9% saline.; Before surgery, 10 milliliter of venous blood was collected from the anticubital fossa of the patients forearm and stored into sterile tubes containing anticoagulant (0.5 milliliter citrate phosphate dextrose) from each patient in the experimental group using routine venipuncture procedure. The whole blood is then centrifuged at 1,200 rotations per minute for ten minutes. The supernatant layer obtained was platelet poor plasma and buffy coat was collected in a new sterile tube and centrifuged again at 1,000 rotations per minute for 10 min. The upper half of the supernatant is removed and the lower half is mixed carefully to get platelet rich plasma. Five drops of mixture of 10 % CaCl2 and 1000 Units bovine thrombin to 2 milliliter Platelet rich plasma to obtain the gel form.; Subsequently, platelet rich plasma gel was placed into the extraction sockets of patients in the group A and wound closure was done using simple interrupted 3.0 black silk sutures.; Wound closure was done using simple interrupted 3.0 black silk sutures.; Patients were advised regular post extraction and prescribed 500 milligram of paracetemol postoperatively (1 tablet every 6 hours for 2 days).
Intervention MeSH terms: Anesthetics
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment