The 2018 Classification of Periodontal Diseases: An Observational Study on Inter-examiner Agreement among Undergraduate Students

Purpose: The objective of the present observational study was to assess the inter-examiner agreement for the diagnosis of periodontitis using the 2018 CPD among fourth and fifth year undergraduate students. It is hypothesised that there is no difference in the inter-examiner relaibility between fourth- and fifth-year undergraduate students regarding staging and grading periodontal disease using the 2018 Classification of Periodontal Diseases (CPD).
Materials and Methods: All participants received training on the 2018 CPD scheme through a mandatory periodontics course conducted by a periodontist. Documentation for seven deidentified periodontitis patients, comprising medical history, dental history including tooth loss, intra-oral photographs and radiographs, periodontal charts reporting probing depth, plaque and bleeding on probing scores, furcation involvement and clinical attachment loss, was sent via e-mail to undergraduate students. The cases consisted of one sextant, and the participants were instructed to assume the sextant to be a true representation of the entire dentition. Power analysis was done on pilot data, and the level of significance was set at p0.05.
Results: The percentage of undergraduate students in the fourth and fifth year that correctly identified the stage of periodontitis according to the 2018 CPD ranged between 28% and 72% and 18.5% and 77.8%, respectively. The percentage of undergraduate students in the fourth and fifth year that correctly identified the grade of periodontitis ranged between 40% and 88% and 51.8% and 92.5%, respectively. The overall staging and grading ranged between 22.8% and 74.1%, and 45.66% and 87.4%, respectively. There was no statistically significant difference between fourth- and fifth-year undergraduate students with regards to assigning the correct diagnoses to case documentation in terms of either stage or grade.
Conclusion: Fourth- and fifth-year undergraduate students demonstrated high inter-examiner agreement using the 2018 CPD. Keywords: classification, diagnosis, inter-examiner agreement, periodontal disease, periodontitis, undergraduate