RESUMEN
BACKGROUND: This cross-sectional study aimed to evaluate the diagnostic accuracy of severe periodontitis by three different case definitions. METHODS: Patients aged >35 years (n = 243, mean age = 47.8 ± 9.3 years) were evaluated by periodontal examinations and classified in patients with severe periodontitis according to the case definition proposed by the Centers for Disease Control and Prevention (CDC) in collaboration with the American Academy of Periodontology (AAP)-CDC/AAP, the new periodontal disease classification proposed jointly by the AAP and the European Federation of Periodontology (EFP/AAP), and the Community Periodontal Index (CPI). The primary outcome was to compare the diagnostic accuracy of severe periodontitis between the three case definitions. Sensitivity (SS), specificity (SP), and area under the receiver operating characteristic (ROC) curve were used to analyze the accuracy. RESULTS: The proportion of subjects presenting the most severe definitions of each classification was: severe periodontitis (CDC/AAP) = 47.3%, type III and IV periodontitis (EFP/AAP) = 43.2% and CPI code 4 = 44.4%. When comparing the CDC/AAP case definitions with the EFP/AAP classification, SS, SP, and ROC of 81.7%, 91.4%, and 0.866 (CI, 95%: 0.816 to 0.916), respectively, were obtained. Similarly, when comparing CDC/AAP to CPI code 4, SS, SP, and ROC of 81.7%, 89.1%, and 0.854 (CI, 95%: 0.802 to 0.906), respectively, were obtained. When type III and IV periodontitis (EFP/AAP) was compared with CPI code 4, the values were 92.4%, 92%, and 0.922 (CI, 95%: 0.883 to 0.961), respectively. CONCLUSIONS: The EFP/AAP classification and the CPI demonstrated high diagnostic accuracy with the CDC/AAP case definition to diagnose severe periodontitis.