We developed a PRG-based predictive model for predicting the probability of periodontitis on the basis of five hub PRGs (charged multivesicular body protein 2B (CHMP2B), granzyme B (GZMB), Z-DNA-binding protein 1 (ZBP1), interleukin (IL)-1β, and interferon regulatory factor 1 (IRF1)) and found that patients could benefit from the model. The gene discussed is IRF1; the disease is periodontitis.