Total Oxidant Status and Bone Resorption Biomarkers in Serum and Gingival Crevicular Fluid of Patients With Periodontitis

Background: In this study, the relationships between total oxidant status (TOS) and receptor activator of nuclear factor-kappa B ligand (RANKL) and osteoprotegerin (OPG) levels and RANKL/OPG ratios in serum and gingival crevicular fluid (GCF) are investigated in patients with chronic (CP) and generalized aggressive (GAgP) periodontitis. Methods: Thirty patients with CP, 30 patients with GAgP, and 28 periodontally healthy controls were included in the study. After clinical measurements and samplings, serum and GCF TOS, RANKL, and OPG levels were determined by a novel automatic colorimetric method and enzyme-linked immunosorbent assays. Results: Serum and GCF TOS, RANKL, and RANKL/OPG values were higher in the periodontitis groups compared with controls, and they were also higher in the GAgP group than the CP group (except serum and GCF RANKL). Furthermore, serum and GCF OPG concentrations were lower in the periodontitis groups than in controls. Strong positive and negative correlations were observed between the periodontal parameters TOS and bone resorption biomarkers. Conclusions: The present results reveal that TOS, RANKL, and RANKL/OPG values are systemically and locally increased in periodontitis and that this increase is more evident in AgP than CP. These findings further suggest that oxidative stress is closely associated with the severity of periodontitis and bone resorption biomarkers.