Fig. 2: Multivariable-adjusted hazard ratios (HRs) for pancreatic cancer in relation to a combination of dental inflammatory conditions and number of teeth by age group.

Time scale is attained age. The Cox models were adjusted for sex, calendar year, family income, education, family history of pancreatic cancer, smoking-related diseases, and alcohol-related disorders and diseases. Dental inflammation includes mild inflammation and periodontitis; no inflammation includes healthy, caries, and root canal infection; no inflammation and ≥28 teeth was the reference group; in the <50 age group, the subgroups having 15–20 and 1–14 teeth were combined into 1–20 teeth due to the small numbers of cancer cases, with the label of “(No) inflammation & 15–20 teeth”. X-axis is logged. P value for interaction was 0.469 in the <50 age group, 0.477 in the 50–70 age group, and 0.772 in the 70+ age group.