It was aimed to evaluate the contributions of T-PRF treatment combined with open flap debridement on biological markers in GCF and periodontal outcomes in chronic periodontitis patients. 29 patients (58 sites) with chronic periodontitis were treated either with autologous T-PRF with OFD or OFD alone. GCF growth factor levels and relative RANKL/OPG ratio at baseline and 2, 4 and 6 weeks postoperatively were analyzed, and clinical parameters such as probing depth (PD), relative attachment level (RAL) and gingival margin level (GML) at baseline and 9 months after surgery were compromised.

A total of 29 medically healthy patients (12 females and 17 males; age range 28-49 years, mean±SD: 38.22±8.21) with chronic periodontitis at the outpatient Ataturk University, Department of Periodontology, Faculty of Dentistry, Erzurum, Turkey, were selected for the study. The study, conducted from November 2015 to June 2016, was planned as a randomized, double-blinded, controlled clinical trial that used a split-mouth design. This study was proved by the ethics committee of Ataturk University Faculty of Dentistry, and all patients received verbal information regarding participation and provided written informed consent for including to the study.

Bone loss characteristics of the patients were diagnosed with full-mouth radiographs and cone-beam computed tomography. This study included the patients with moderate-to-severe chronic periodontitis with a probing depth of 5 mm or deeper and horizontal bone loss (one- or two-wall shallow interproximal defects) of at least two quadrants of the jaws after Phase-I periodontal therapy. After re-evaluating the results of Phase-I therapy, patients with any of the following were excluded from the study: 1) smoking or tobacco use in any form; 2) medications known to affect periodontal treatment and blood coagulation; 3) systemic conditions known to affect periodontal status; 4) pregnancy/lactation; and 5) poor oral hygiene (plaque index [PI] >1.5) (Sillness and Loe; 1964). Patients with teeth with 3-wall intrabony defects, gingival recession, endodontic lesion, or furcation involvement were also excluded.

Inclusion Criteria:

• Patients with CP who had pocket depth ≤ 5 mm and at least two area (grouped as Control and PRF) with horizontal bone loss after initial treatment

Exclusion Criteria:

• The subjects excluded in the study had history of systemic disease, were smokers, had allergy to any drug, had need for prophylaxis of antibiotic and had taken antibiotics at least 6 months