Document Type : Original Article



Background: Recurrent aphthous stomatitis (RAS) is among the most common oral lesions and pain is often the chief complaint of patients. The main etiology of RAS is unknown but several predisposing factors have been suggested. This study aims to assess the correlation of blood types (ABO/Rh) with RAS. Methods: We conducted this prospective screening study on 50 patients with RAS and 50 controls. Both groups received a questionnaire and underwent serum screening for detection of blood t