Evaluation of oxidative stress and antioxidant profile in patients with oral lichen planus

Objective: The aim of this study was to assess oxidative stress and antioxidant profile in patients with oral lichen planus (OLP) using serum and salivary samples and to compare these biomarkers in a group of healthy subjects. Patients and methods: Twenty-one recently diagnosed patients with OLP and 20 healthy controls with matched periodontal status were recruited to the study. Total antioxidant activity (TAA) and lipid peroxidation product malondialdehyde (MDA) in both serum and saliva were determined. Univariate comparisons between the two groups were made for quantitative and categorical variables to determine any significant differences. Results: In OLP patients, total antioxidant defense (TAA) was significantly lower than that in healthy subjects in their serum samples (P = 0.01). Salivary MDA levels were significantly higher in the OLP group compared with healthy subjects (P = 0.03). A significant correlation was found between serum and saliva TAA estimates in patients with OLP (r = 0.714 and P = 0.0001) and in the control group (r = 0.69 and P = 0.001). Significant correlation was also found between serum and saliva MDA values in control group (r = 0.464 and P = 0.04). A significant inverse correlation was found between salivary MDA and TAA values in the control group (r = -0.598 and P = 0.005). Conclusions: The findings of this study suggest an increased oxidative stress and imbalance in the antioxidant defense system in biological fluids of patients with OLP. These findings may reflect the disease phenomenon of OLP rather than a causal effect and their role in pathogenesis and transformation of OLP to cancer, if any, needs further elucidation.