Lipid peroxidation levels and total oxidant/antioxidant status in serum and saliva from patients with chronic and aggressive periodontitis. Oxidative stress index: A new biomarker for periodontal disease?

Background: In this study, levels of malondialdehyde (MDA), which is a significant product of lipid peroxidation (LPO), total oxidant status (TOS), total antioxidant capacity (TAOC), and the oxidative stress index (OSI), a novel value as a marker of periodontal disease activity, are investigated in serum and saliva from patients with chronic (CP) and generalized aggressive (GAgP) periodontitis. Methods: A total of 98 patients (33 with CP, 35 patients with GAgP, and 30 periodontally healthy controls) enrolled in the study. After clinical measurements and sample collection, the MDA level, TOS, and TAOC were measured by high-performance liquid chromatography and a novel automatic colorimetric method. The OSI was calculated as [(TOS/TAOC) × 100]. Results: Although the salivary MDA levels and serum and salivary TOS and OSI values were significantly higher in the periodontitis groups than in the control group (P <0.05), the serum and salivary TAOC levels were significantly lower, and no significant difference in serum MDA levels was found (P >0.05). Furthermore, oxidative stress parameters were higher in the GAgP group than in the CP group (except the serum and salivary MDA levels and serum TAOC). Significant positive and negative correlations were observed between periodontal parameters and the MDA levels and TOS, TAOC, and OSI values (except serum MDA) (P <0.05). Conclusions: The present findings suggest that an increased TOS and decreased TAOC, rather than LPO, play important roles in the pathology of periodontitis and are closely associated with clinical periodontal status. Furthermore, the OSI may be a useful and practical parameter for evaluating periodontal disease activity.