en تخصصي Special پژوهشي Research <strong>Objective:</strong> Type 2 diabetes mellitus (T2DM) is a multifactorial disorder with various disturbances in biochemical processes such as antioxidant status and lipid peroxidation. The aim of present study was evaluation of the oxidative stress markers in saliva of T2DM patients.<br> <strong>Materials and Methods</strong><strong>:</strong> In this study, 80 (40 T2DM and 40 control) individuals were assessed. The salivary total antioxidants capacity and lipid peroxidation were determined by the ferric reducing antioxidant power (FRAP) method and Thiobarbituric acid reactant substances (TBARS) assay, respectively.<br> <strong>Results:</strong> Total salivary antioxidants value was significantly lower in T2DM patients compared with healthy controls (<em>P</em> -value: 0.01). A significant increase in lipid peroxidation was seen in T2DM (<em>P</em>-value: 0.0001).<br> <strong>Conclusion</strong><strong>:</strong> The findings of the present study suggest that diabetic patients confront a disturbed state of antioxidant defense, especially the reduction in total antioxidant capacity of body. Lipid peroxidation, Saliva, Total antioxidant capacity, Type 2 diabetes mellitus 88 93 http://ijdo.ssu.ac.ir/browse.php?a_code=A-10-30-201&slc_lang=en&sid=1 Mehryar Zargari No Department of Biochemistry Biophysics and Genetics, Faculty of Medicine, Molecular and Cell Biology Research Center, Mazandaran University of Medical Sciences, Sari, Iran. Hourolein Arab No Department of Biochemistry Faculty of Medicine, Babol University of Medical Sciences, Babol, Iran. Zahra Ghafouri Yes Department of Biochemistry Biophysics and Genetics Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran