Systematic review and meta-analysis of oxidative stress and antioxidant markers in recurrent aphthous stomatitis

We performed this systematic review and meta-analysis to synthesize all studies that reported the level of oxidative and antioxidative markers in recurrent aphthous stomatitis (RAS) patients compared to controls.

We registered our study in PROSPERO (CRD42023431310). PubMed, ProQuest, Scopus, EMBASE, Google Scholar, and Web of Science were searched to find relevant publications up to June 5, 2023. The standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated. We included 30 articles after multiple stags of screening.

We found that erythrocyte superoxide dismutase and Glutathione peroxidase activity were significantly lower in patients with RAS compared to healthy controls (SMD = − 1.00, 95%CI = -1.79 to -0.21, p = 0.013, and SMD = − 1.90, 95%CI = -3.43 to -0.38, p = 0.01, Respectively). However, there was not any difference between patients with RAS and healthy controls in erythrocyte Catalase (SMD = − 0.71, 95%CI = -1.56–0.14, p = 0.10). The total antioxidant status (TAS) level, in serum was significantly lower in patients than healthy controls (SMD = − 0.98, 95%CI = -1.57 to -0.39, p = 0.001). In addition, RAS patients had higher levels of serum Malondialdehyde (MDA), Serum total oxidant status, and serum oxidative stress index than healthy controls (SMD = 2.11, 95%CI = 1.43–2.79, p < 0.001, SMD = 1.53, 95%CI = 0.34–2.72, p = 0.01, and SMD = 1.25, 95%CI = 0.25–2.25, p = 0.014, Respectively); However, salivary MDA and TAS, and serum uric acid, vitamin E and C, and reduced glutathione levels of patients with RAS were not different from that of healthy controls.

The relationship between oxidative stress and RAS is well established in this meta-analysis. Although the molecular processes underlying the etiology of this pathology remain unknown, evidence indicating oxidative stress has a significant role in the pathogenesis of RAS has been revealed.