IRCT201709211081N8 IRCT 2017-10-02 Private clinic, Dr. Golpar Radafshar, associate professor of periodontology, Guilan University of Me How periodontal treatment affects oral health-related quality of life in patients with chronic periodontitis Effects of one-stage full mouth disinfection versus periodontal surgery on oral health-related quality of life in patients with chronic periodontitis 2017-10-15 anticipated 40 Complete https://irct.ir/trial/102 interventional Randomization: N/A, Blinding: Double blinded, Placebo: Not used, Assignment: Single, Purpose: Treatment, Other design features: The original OHIP-49 questionnaire was validated and standardized for Iranian population using CVI and CVR. Some questions did not meet the appropriate CVI or CVR and were deleted. The resultant questionnaire with 35 items was used in this study. 2-3 Chronic periodontitis. Intervention 1: Non-surgical periodontal treatment based on Quirynen protocol of one stage full mouth disinfection comprised of scaling and root planing with Chx 0.2% pocket irrigation completed within 24 hours. Intervention 2: Surgery comprised of flap debridement with minor osseous surgery on a quadrant basis over single or multiple treatment episodes, according patient’s treatment needs. In case of multiple sessions, a minimum of 2-week interval was considered.