Comparison of two different periodontal risk assessment methods with regard to their agreement: Periodontal risk assessment versus periodontal risk calculator

Aim To evaluate the level of agreement between the periodontal risk assessment (PRA) and the periodontal risk calculator (PRC). Materials and methods Periodontal risk was retrospectively assessed among 50 patients using PRA and PRC. Both methods were modified. PRA by assessing probing pocket depths and bleeding on probing at four (PRA4) and six (PRA6) sites per tooth, PRC by permanently marking or unmarking the dichotomously selectable factors irregular recall, oral hygiene in need of improvement and completed scaling and root planing for PRC. Agreement between PRA and PRCred (summarized risk categories) was determined using weighted kappa. Results Fifty patients enrolled in periodontal maintenance (48% female, age: 63.8 +/- 11.2 years) participated. PRA4 and PRA6 matched in 32 (64%) patients (kappa-coefficient = 0.48,p < .001). There was 100% agreement between both PRC versions. There was minimal agreement of PRA6 and PRCred (66%, 28% one different category, 6% two different categories; kappa-coefficient = 0.34;p = .001). PRA4 and PRCred did not match (60% agreement, 34% one different category, 6% two different categories; kappa-coefficient = 0.23;p = .13). For the SPT diagnosis of severe periodontitis, PRA6 and PRCred agreed weakly (kappa-coefficient = 0.44;p = .004). Conclusion PRA and PRC showed a minimal agreement. Specific disease severity may result in improved agreement.