Periodontitis, Edentulism, and Risk of Inflammatory Bowel Disease (IBD): A Systematic Review With Meta-Analysis

To systematically evaluate whether periodontitis and edentulism are associated with the presence or development of inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), and to additionally assess evidence relating periodontitis to IBD activity and severity.

A systematic search of MEDLINE, Embase, Scopus, and Web of Science, supplemented by manual searches, was conducted through February 2026. Cohort and cross-sectional studies assessing periodontitis or edentulism in relation to IBD were included. Risk of bias was evaluated using the Newcastle-Ottawa Scale. Meta-analyzes were performed separately for longitudinal and cross-sectional studies using random-effects models, with subgroup and sensitivity analyzes conducted where appropriate.

Twenty-two studies met the eligibility criteria, including 6 cohort studies and 16 cross-sectional studies, comprising 12 627 564 participants. In cohort studies, periodontitis was associated with a trend toward increased incident IBD overall (RR 1.25; 95% CI 0.98-1.58), although statistical significance was not reached, while no significant association was observed for CD (RR 1.05; 95% CI 0.86-1.29). In contrast, a significant association emerged between periodontitis and incident UC (RR 1.18; 95% CI 1.07-1.31). No longitudinal estimates were available for severe periodontitis or edentulism. In cross-sectional studies, periodontitis was significantly associated with prevalent IBD (OR 2.11; 95% CI 1.53-2.93), CD (OR 2.02; 95% CI 1.59-2.55), and UC (OR 2.48; 95% CI 1.71-3.59). Severe periodontitis was also associated with UC in a limited number of studies, whereas evidence regarding edentulism was scarce and inconsistent. Evidence linking periodontitis to IBD activity or severity was more limited and heterogeneous, although several studies suggested associations with markers of disease burden.

Longitudinal evidence suggests that periodontitis has a modest association with incident UC, whereas associations with IBD overall and CD appeared weaker and less consistent. At the same time, cross-sectional studies consistently support the coexistence of periodontitis and IBD, possibly reflecting shared susceptibility, bidirectional interactions, or common oral-gut inflammatory pathways. Whether periodontitis contributes to IBD burden or disease expression over time warrants further longitudinal and mechanistic investigation.