The effect of diabetes on tooth loss caused by periodontal disease: A nationwide population‐based cohort study in South Korea

BACKGROUND: Our purpose was to compare the risk of tooth loss caused by periodontal disease between diabetic and nondiabetic individuals and to estimate the relative risk of tooth loss according to the severity and control of diabetes. METHODS: We selected 10,215 individuals who were diagnosed as diabetics in the Korean National Health Insurance Service-National Sample Cohort (NHIS-NSC) database in 2003 and the same number of individuals who had never been diagnosed with diabetes during the period covered by the NHIS-NSC (2002-2013) with propensity score matching. Diabetic individuals were divided into two groups according to the treatment modality. We counted the number of teeth lost in each group to determine the difference in the risk of tooth loss among groups and used the Cox proportional hazards model to calculate hazard ratios (HRs) of tooth loss caused by periodontitis. RESULTS: Diabetic individuals had a higher risk of tooth loss than nondiabetic individuals (HR = 1.298, 95% confidence interval [CI]: 1.233 ≤ HR ≤ 1.366; P < 0.01). The severer the degree of diabetes, the higher the risk of tooth loss. As the number of dental visits increased, the risk of tooth loss declined (HR = 0.998, 95% CI: 0.996 ≤ HR ≤ 0.999; P < 0.01). CONCLUSIONS: Within the limits of this retrospective cohort study, the risk of tooth loss among diabetic individuals was higher than that among nondiabetic individuals. The risk of tooth loss declined with increasing numbers of dental visits and increased with the severity of diabetes.