Comparison Between the 2017 EFP/AAP and CDC/AAP Case Definitions on Periodontal Status and Their Association With Risk Factors in an Adult Norwegian Population-Insights From the Tromsø Study: Tromsø7.

Objectives: To describe the prevalence, extent and severity of periodontitis in an adult Norwegian population, using the 2017 EFP/AAP and CDC/AAP case definitions, and their associations with potential risk factors for periodontitis. A secondary aim was to explore how the stage and grade of periodontitis shifted when complexity and risk factors were added.

Material and methods: A subsample of participants (≥ 40 years, n = 21,083) in a cross-sectional health study (Tromsø7, 2015-2016) was invited to an oral health examination (n = 3946). Radiographic bone loss and four site measurements of periodontal probing depth (PPD) and bleeding on probing were recorded for 3701 adults.

Results: According to EFP/AAP, 89% of participants had periodontitis (21% stage III-IV), while 74% had periodontitis defined by CDC/AAP (12% severe periodontitis). Five percent of stage III/IV cases and 22% of severe cases had generalised disease. Higher age, frequent use of dental care, smoking and higher body mass index were associated with periodontitis for both definitions. PPD contributed to a shift to more severe stages. Smoking contributed the most to the shifting of grade, with 7% of cases shifting to grade C.

Conclusions: Periodontitis was highly prevalent according to both case definitions. Associations with known risk factors remained relatively consistent between the two case definitions. Complexity and risk factors played a significant role in the shifting of stage and grade of periodontitis.