Serum prolidase and oxidative stress levels in patients with recurrent aphthous stomatitis: a prospective, controlled study

Background: Recurrent aphthous stomatitis is a common disease characterized by single or multiple, self-healing, well-circumscribed, periodic ulcers occurring in the oral cavity. Although the relationship between recurrent aphthous stomatitis and oxidative stress has been extensively reviewed in the past, its relationship with prolidase enzyme levels has not been previously investigated. Aim: The aim of this study is to investigate plasma antioxidant status and prolidase enzyme levels in patients with recurrent aphthous stomatitis. Methods: The serum total oxidant status, total antioxidant status, oxidative stress index, prolidase and paraoxonase levels of 34 recurrent aphthous stomatitis patients (mean age 35.1) and 34 healthy controls (mean age 37.7) were compared in this study. Results: Total oxidant status was significantly higher in the recurrent aphthous stomatitis group (P < 0.005). The mean total oxidant status value was 5.19 mmol/L in the recurrent aphthous stomatitis group, while it was 2.90 mmol/L in the control group. Oxidative stress index was significantly higher in the recurrent aphthous stomatitis group (P = 0.016*). The mean oxidative stress index level was 0.28 AU in the recurrent aphthous stomatitis group, while it was 0.18 AU in the control group. When control and patient groups were compared, there was no significant difference between groups with regard to the total antioxidant status (P = 0.343). The total antioxidant status levels were 1.09 and 1.14 mmol/L in control and patient groups, respectively. There was no statistically significant difference between PON1 levels of recurrent aphthous stomatitis and control groups (P = 0.218). Mean PON1 levels were 326 U/L in the recurrent aphthous stomatitis group and 381 U/L in the control group. Prolidase levels were not significantly different between recurrent aphthous stomatitis and control groups (P = 0.955). The mean prolidase level was 219.79 U/L in the recurrent aphthous stomatitis group and 219.26 U/Lin the control group. Limitations: The limitation of this study is the small size of both patient and control groups and exclusion of pediatric patients., Similar studies performed in pediatric patient populations with a comparison to adults may be useful in providing meaningful results. Conclusions: We detected that the total oxidant status and oxidative stress index was higher in patients with recurrent aphthous stomatitis as compared to healthy controls. We could not demonstrate a significant difference in total antioxidant status, PON1 and prolidase values.