The new periodontal disease classification: Level of agreement on diagnoses and treatment planning at various dental education levels.

Purpose/objectives: Using the periodontal diseases classification published in 2018, this study evaluated the level of agreement among predoctoral and postgraduate students of different education levels and specialties in the diagnosis and treatment planning of periodontal conditions.

Methods: Second-year (D2) and fourth-year (D4) dental students, postgraduate orthodontic students (OS), and periodontology students (PS) were presented with an anonymous survey of 10 cases, each with five choices of diagnosis and seven therapeutic approaches. The cases included a patient summary, photographs, radiographs, periodontal charting, and ranged from health to periodontitis. Consensus diagnosis, used as a gold standard, was established between two experienced periodontists. Diagnosis and treatment choices for each case were compared across educational groups using Fisher's exact test. The level of agreement among educational groups was assessed using a multirater kappa coefficient.

Results: The survey was completed in 2020 with a 72.4% overall response rate (57-D2, 45-D4, 17-OS, and 12-PS). The overall level of agreement on diagnosis was fair (κ = 0.24, p <.0001) with PS showing the most agreement (κ = 0.55, p <.0001). There were tendencies to prioritize stage over grade and extent in assigning diagnoses and to overdiagnose disease severity and underdiagnose localized periodontitis. Nonsurgical periodontal therapies had the highest overall agreement (κ = 0.63 for scaling/root planing and κ = 0.44 for maintenance, p <.0001). Response distribution per case and per level of education indicated that PS more consistently agreed with the gold standard than any other group.

Conclusions: OS, D2, and D4 students demonstrated inferior agreement levels compared to PS, successfully recognized health from disease, suggested appropriate treatment plans, and tended to overdiagnose milder periodontal conditions.