Tehran University of Medical Sciences Journal of Craniomaxillofacial Research 2345-5489 3 1 2015 03 15 157 160 EN Shamsolmolouk Najafi Department of Oral Medicine, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. Arghavan Tonkaboni Department of Oral Medicine, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. Mahsa Mohammadzadeh Dentist 2016 09 15 2016 09 15 Introduction: Recurrent aphthous stomatitis (RAS) is a common disease with unknown etiology and no treatment. The purpose of this study is to assess the relationship between serum antioxidants level and clinical manifestation. Change in antioxidant level can lead inflammatory reaction through oxidative stress. Materials & Methods: A total 50 patients were selected for this cross sectional study. Superoxide dismutase (SOD), glutathione peroxidase (GSHPX) and total antioxidant status (TAS) was measured in plasma. Also pain intensity based on the visual analogue scale (VAS), the mean interval between lesion, number of lesions and the mean duration of complete healing were recorded. Statistical analysis was performed by using spearman, chi square and T-test. Results: We had 50 patients include 28 female and 22 male. Mean and standard deviation was for TAS (1.35±0.15), GPX (178.42±39.67) and SOD (257.86±63.17). Number of lesion and duration of RAS had direct relationship with pain severity. Pain intensity and GPX and SOD were significant (respectively 0.05, 0.04). GPX and SOD level was indirectly related (p=0.04). Conclusion: We could show that RAS patients had alteration in SOD and GPX level but TAS level was stable. Against TAS level which had no change, with more lesion and severe pain GPX level is lower and SOD level was higher. These two antioxidants were related indirectly. Key Words: Recurrent aphthous stomatitis, Antioxidants, Symptoms, Superoxide dismutase (SOD), glutathione peroxidase (GSHPX), total antioxidant status (TAS). https://jcr.tums.ac.ir/index.php/jcr/article/view/70 https://jcr.tums.ac.ir/index.php/jcr/article/download/70/122