Cigarette smoke contains various oxygen-free radicals which are considered as the main causes of damage to biomolecules when exposed to cigarette smoke. Saliva is the first biological fluid that encounters inhaled cigarette smoke (CS) and has an antioxidant defense system able to counter toxic activities of free radical species. So, the aim of this study was to compare the levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in saliva of smokers and nonsmokers.

Unstimulated saliva of 200 males (100 smokers and 100 nonsmokers) was collected. The saliva was centrifuged and the activity of salivary superoxide dismutase and glutathione peroxidase was measured according to a specific assay.

The mean value of superoxide dismutase activity was significantly higher in the smoking group than in the nonsmoker group, while the levels of GSH-Px activity was significantly higher in the nonsmoking group than in the smoking group.

Cigarette smoke leads to an alteration in salivary antioxidant activity. Evaluating the variations in the level of antioxidant enzymes (SOD and GSH-Px) in smoker's saliva might be useful for estimating the level of oxidative stress caused by cigarette smoke. Thus, it may help in patient's education regarding the ill-effects of smoking and determining the evolution and progress of various oral diseases.

Saggu TK, Masthan KMK, Dudanakar MP, Nisa SUI, Patil S. Evaluation of Salivary Antioxidant Enzymes among Smokers and Nonsmokers. World J Dent 2012;3(1):18-21.