Myllymäki V, et al. - Experts sought to study whether the periodontal condition is related to the development of type 2 diabetes mellitus (T2DM). For the development of T2DM, a predictor may be the poor periodontal condition. Nonetheless, the periodontal condition and the development of T2DM demonstrated uncertain causality. Compared to dentate subjects without deepened periodontal pockets, the adjusted rate ratios (RR) with 95% confidence intervals for the incident T2DM, were 1.32, 1.56 and 1.00 among subjects with 4–5 mm deep periodontal pockets, among subjects with 6 mm deep or deeper periodontal pockets, and among edentulous subjects, respectively.