JUP and periodontal disorder: In addition, when we analyzed receiver operating characteristics (ROC) curves for periodontal disease (presenting of PD ≥4 mm), the optimal cut-off point of titers against Pg was 7.75 (1.68 in Kudo et al.)and sensitivity, specificity, and the areas under the ROC curve were 0.663, 0.638, and 0.691.