Abstract Background Periodontitis is common in patients with inflammatory bowel disease (IBD), but its impact on disease course is unclear. We aimed to determine whether periodontal inflammatory burden predicts clinical worsening of IBD in a realworld setting. Methods We conducted a prospective cohort study at the Turin IBD Clinic. Twohundredfiftysix adults with Crohn’s disease (66 %) or ulcerative colitis (32 %) underwent a comprehensive periodontal examination (probing pocket depth, clinical attachment level, bleeding on probing) between September 2020 and December 2021. Periodontal inflammation was quantified by the number of sites with pockets ≥ 6 mm and by the Periodontal Inflamed Surface Area (PISA), dichotomised at the median (high 500 mm²). The composite outcome comprised need for systemic steroids, initiation/escalation or discontinuation of target therapy, hospitalization, or surgery within 30 months. Associations were tested using multivariable logistic regression and Cox models adjusted for age, sex, smoking, IBD type, previous surgery, and baseline therapy. Results After 2.3 ± 0.7 years, 105/256 patients (41 %) experienced clinical worsening. The highPISA group showed higher rates of steroid use (27 % vs 9 %), hospitalisation(17 % vs 2 %), and surgery (15 % vs 6 %), all p 0.05. Each 100mm² increase in PISA was associated with an adjusted odds ratio (OR) of 1.41 (95 % CI 1.23–1.61); high PISA remained the strongest predictor (OR 26.7; adjusted hazard ratio 8.33). The number of pockets ≥ 6 mm was also associated with worsening (OR 1.09 per site, p = 0.018). Older age (OR 0.95) and clinical remission at baseline (OR 0.28) were protective. Conclusion A large inflamed gingival surface is an independent marker of IBD worsening. Integrating periodontal assessment and control into routine IBD management could help reduce flares and guide personalised therapeutic strategies. Conflict of interest: Prof. Ribaldone, Davide Giuseppe: No conflict of intereset Romano, Federica: Muwalla, Mamdouh: Mazza, Francesca: Bebars, Ahmad: Perotto, Stefano: Zaccardi, Benedetta: De Vita, Francesca: Vernero, Marta: Aimetti, Mario: Baima, Giacomo:
Ribaldone et al. (Thu,) studied this question.