Oral microbiota in active and passive states of recurrent aphthous stomatitis: An analysis of case-control studies

This study was presented to reveal the most distinct microbial prevalence in recurrent aphthous stomatitis (RAS) lesions compared to healthy controls. The case-control studies were selected in electronic databases until Nov 2022 with key search terms, and the eligible publications were screened and analyzed by independent authors. A total of 14 studies were identified, which included 531 cases of active states of RAS (AS-RAS), 92 cases of passive states of RAS (PS-RAS) and 372 healthy controls. The most sample pattern was the mucosa swab performed in 8 of 14 studies, biopsies in 3 studies, followed by micro-brush, and saliva. A variety of bacteria in higher or lower abundance were observed in RAS lesions. The etiopathogenesis of RAS may not be ascribed to a single pathogen. A possible explanation is that microbial interactions modify immune response or destroy the epithelial integrity, thus contributing to the development of the condition.