Effect of Leucocyte and Platelet Rich Fibrin as an Adjuvant in Non-Surgical Periodontal Therapy: A Split-Mouth Randomized Controlled Clinical Trial

Materials and Methods Study design and Patient Selection A split-mouth, randomized controlled clinical trial enrolling 13 patients (8 males and 5 females, mean age 52.3 ± 9.4 years) was set-up. The patients were informed about the benefits and risks of the study and each participant signed informed consent.

Non-surgical periodontal treatment A single periodontist (L.C.) performed all periodontal treatments. NSPT consisted of two sessions of scaling and root planing (SRP) within 48 hours under local anesthesia using ultrasonic and hand instrumentation. Additionally, the sites associated with PPD ≥ 6 mm in the quadrant assigned to the test group were irrigated with L-PRF exudate and filled with longitudinal pieces of L-PRF membrane. The patients received instructions about soft diet, a carefully and soft mouth rinse with chlorhexidine 0.12%, and no toothbrushing during 7 days in order to avoid the L-PRF removal. After this period, the following instructions were given: modified Bass brushing technique, dental floss, and interdental brushes, and chlorhexidine 0.12% mouth rinse for an extra 7 days. Strict hygiene control by the clinician was also performed in each appointment.

L-PRF membrane preparation Two samples of venous blood were collected in 2 vacutainer tubes (red cup) of 10 ml without anticoagulant. They were centrifuged at 408 g for 12 minutes using a table centrifuge (IntraSpinTM, Intralock®, Florida, USA) according to the protocol described by Temmerman et al.18 The L-PRF clots were removed from the tube, separated from the red cells and placed in the Xpression box (IntraSpinTM, Intralock®, Florida, USA) to gently compress them in membranes. The membranes were chopped in longitudinal pieces to fill the periodontal pockets ≥ 6mm. The exudate, released during the compression, called L-PRF exudate was aspirated to rinse the treated pockets. (Figure 1)

Clinical Measurements All clinical measurements were performed by a single trained and calibrated examiner (N.J.) who was masked for the treatment assigned, using a basic examination instrument kit and a University of North Carolina no. 15 color-coded periodontal probe. The following clinical parameters were measured at baseline and 6 weeks, 3 months and 6 months after treatment: probing pocket depth (PPD), clinical attachment level (CAL), gingival recession (GR), bleeding on probing (BOP), and O´Leary plaque index (PI).19 Additionally, the root sensitivity (RS) was evaluated using a 100-mm visual analogue scale (VAS) (0 indicating no pain, 50 indicating average, and 100 indicating an unbearable pain) at 24 hrs., 6 weeks, 3 months, and 6 months after treatment. The change in PPD, CAL, GR, BOP, PI, and RS (difference between baseline measures and at 1, 3, and 6 months) were calculated.

GCF collection GCF samples were collected from the deepest pocket from each quadrant before recording the clinical measurement (baseline, and 6 weeks and, 3 months after treatment) in order to evaluate the concentration of Porphyromona gingivalis (P.g), Aggregatibacter actinomycetemcomitans (A.a), Prevotella intermedia (P.i) and Fusobacterium nucleatum (F.n). The sample area was isolated with cotton rolls, and contamination with saliva was avoided using an appropriate suction and air spray. Then, an endodontic #35 paper-point was inserted until a slight resistance was felt and it was held for 30 seconds. The paper-points were immediately inserted in an Eppendorf tube and stored at -80ºC for future analysis.