Salivary malondialdehyde in oral submucous fibrosis – A marker for oxidative damage

Background: Oral submucous fibrosis (OSMF) is a potentially malignant disorder of oral mucosa and its malignant transformation rate accounts to about 7%–13%. Oxidative damage and lipid peroxidation plays an important role in OSMF. Lipid peroxidation has not been widely investigated in OSMF patients with respect to clinical staging and histopathological grading. As human saliva is a diagnostic fluid which can be obtained in a noninvasive procedure as compared to the blood for serum analysis, the present study was aimed at evaluating the salivary malondialdehyde (MDA) levels in OSMF and comparison with respect to clinical staging and histopathological grading. Aim: This study aims to evaluate salivary MDA levels in OSMF and compare the levels with respect to clinical and histopathological grading systems. Materials and Methods: Forty cases of clinically diagnosed and histopathologically proven cases of OSMF were included for the purpose of this study. As controls 40 age-matched individuals without any systemic disease were selected. Unstimulated whole saliva was collected from each individual, centrifuged and frozen at − 20°C until analysis. Lipid peroxidation products MDA were analyzed by thiobarbituric acid reaction. Results: Salivary MDA levels were significantly increased in OSMF patients compared to controls. The progressively increased salivary MDA levels showed a positive correlation with the clinical stages and histopathological grades of OSMF and the results were statistically significant. Conclusion: The increased salivary MDA levels in OSMF patients compared to the control group suggests an increased oxidative stress levels in the potentially malignant disorders such as OSMF. The mean salivary MDA levels were increased significantly as the clinical stage and histopathological grade of OSMF advances, suggesting MDA to be used as a reliable biochemical marker and also a prognostic marker to assess the extent of oxidative damage in OSMF.