Oral microbiome and inflammatory bowel disease: A scoping review

To examine the association between the oral microbiome and IBD in terms of microbiota diversity, composition, function, and diagnostic potential through a scoping review of the existing literature.

This scoping review was structured following the PRISMA-ScR guidelines. Literature searches were conducted in PubMed, Embase, and the Cochrane Library, with the time frame restricted from database inception to November 17, 2025.

This review included 31 studies, among which seven topics for patients with periodontitis and IBD-related periodontitis, three studies assessed single bacterial species, and the remaining 21 articles explored the diversity and phylum-level taxonomic shifts of oral microbiota in IBD patients, functional and metabolic pathway alterations associated with oral dysbiosis, as well as the diagnostic potential and biomarkers derived from oral microbial profiles.

The oral microbiota of IBD patients exhibits characteristic dysbiosis, manifested by the enrichment of pathogenic taxa, depletion of anti-inflammatory species, and metabolic dysfunction, which are closely associated with gut microbial alterations and systemic inflammatory status. The salivary microbiome demonstrates significant diagnostic potential for IBD.