Impact of Various Detectable Interdental Clinical Attachment Loss Thresholds on the Estimated Prevalence, Stage and Extent of Periodontitis Based on the EFP / AAP Definition

ABSTRACT Aims To investigate the influence of different detectable interdental clinical attachment loss (CAL) thresholds on estimated prevalence, stage and extent of periodontitis and to assess the influence of three methods in upgrading stage III cases to stage IV in completed surveys. Materials and Methods National Health and Nutrition Examination Survey 2011–2014 data of 7651 adults were used. The CDC/AAP definition and the EFP/AAP definition with interdental CAL of 1, 2, 3 and 4 mm as the detectable threshold were applied. Three methods (< 10 opposing pairs of natural teeth, < 20 remaining natural teeth or < 10 remaining natural teeth in one jaw) were used to upgrade stage III cases to stage IV. Results Estimated periodontitis prevalence was 37.0%, 92.6%, 91.7%, 66.7% and 32.9% using the CDC/AAP definition and the EFP/AAP definition, with 1‐, 2‐, 3‐ and 4‐mm thresholds, respectively. As the threshold increased, stage I/II cases decreased, resulting in higher estimated disease extent in stage II cases. Compared with the use of 20 remaining teeth, the use of 10 opposing pairs yielded a nearly 4% increase in the estimated prevalence of stage IV cases. Conclusions Different detectable thresholds and opposing pair approximation methods could influence estimated periodontitis prevalence, stage and extent.