IRCT2013051313312N1 IRCT 2013-08-04 Vice chancellor for research, Tabriz University of Medical Sciences Comparison of One-Stage Full-Mouth Disinfection and Quadrant-Wise Scaling and Root Planing Comparison of the effects of one-stage full-mouth disinfection and quadrant-wise scaling and aoot planing on serum levels of IL-27 and clinical parameters following treatment of moderate-to-severe chronic periodontitis 2012-08-05 anticipated 40 Complete https://irct.ir/trial/13203 interventional Randomization: Not randomized, Blinding: Not blinded, Placebo: Used, Assignment: Parallel, Purpose: Treatment. N/A chronic periodontits. Intervention 1: After blood samples were taken in the test group , the entire oral cavity was cleaned by an ultrasonic scaler in two sessions in less than 24 hours in order to decrease pathogenic organisms’ counts. Subgingival irrigation of all the pockets was carried out with 0.2% chlorhexidine using an insulin syringe in order to remove all remaining bacteria. An antiseptic agent (0.2% chlorhexidine) was used to brush the dorsum of the tongue to decrease the bacterial load in the area; an antiseptic mouthwash (0.2% chlorhexidine) was used to reduce bacterial load in the saliva and on the tonsils. Intervention 2: The control group patients underwent scaling and root planing procedures at two-week intervals for each quadrant after blood samples were taken.