The Oral Microbiota and Its Implications for Inflammatory Bowel Disease: A Literature Review

Inflammatory bowel disease (IBD) encompasses Crohn's disease (CD) and ulcerative colitis (UC) and represents a heterogeneous spectrum of chronic intestinal inflammation with no exclusive etiology. Emerging evidence underscores that IBD arises from complex interactions between host factors and microbial communities. The disruption of microbial homeostasis facilitates the colonization and invasion of opportunistic pathogens within the gut, precipitating an exaggerated host immune response and driving disease progression. While extensive research has elucidated the role of the gut microbiota in IBD pathogenesis, the contribution of the oral microbiota to this process is garnering increasing attention. Oral microbes can translocate to the intestine via the swallowing of saliva, and harmful oral bacteria and proinflammatory immune cells from the oral mucosa may migrate to the gut, eliciting immune activation. This review explores the emerging role of the oral microbiota in IBD pathogenesis and synthesizes recent advancements in understanding the intricate relationship between oral microbial communities and IBD.