Effect of Non-Surgical Therapy on Receptor Activator Level of Salivary Nuclear Factor Kappa B Ligand and Osteoprotegerin in Chronic Periodontitis: A Prospective Cohort Study

Abstract

Introduction: The receptor activator of NF-kB ligand (RANKL) and osteoprotegerin (OPG) are molecules that play a significant role in bone resorption. The aim of this study was to evaluate the effect of periodontal therapy on the salivary levels of RANKL, OPG, and their relative ratio in patients with chronic periodontitis. Materials and Methods: This prospective cohort study was conducted and twenty-five patients with chronic periodontitis and 25 volunteers with healthy periodontium were recruited in this study. All the patients received scaling and root planing (SRP) combined with oral hygiene instructions (OHI).  Five mL unstimulated saliva sample was collected from all individuals at baseline and four weeks after periodontal therapy. Salivary RANKL and OPG concentrations were determined by enzyme -linked immunosorbent assays (ELISA). Demographic and clinical vari¬ables were compared between the groups using Fisher’s exact test. Comparisons of indices and analyses between the test and control groups were performed by independent t-test and Mann-Whitney U test. The correlations between the salivary and periodontal parameters were evaluated by Spearman correlation coefficient test. Results: SRP improved all examined clinical parameters, and the RANKL concentration and sRANKL/OPG ratio decreased significantly in the saliva after the treatment (p=0.012 and p=0.011). However, no significant change was found for OPG (p=0.840). Conclusion: Our observations indicated that non-surgical periodontal treatment significantly reduced the RANKL and sRANKL/OPG levels. Salivary levels of RANKL and sRANKL/OPG reflected the disease response to therapy, which is suitable for monitoring the results of periodontal treatment