Periodontitis staging and grading, in brief

The 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions, organised by the American Academy of Periodontology and the European Federation of Periodontology, replaced the earlier distinction between “chronic” and “aggressive” periodontitis with a single disease described along two axes.

Stage: how severe and complex

Stage I to IV describes the severity of the disease and the complexity of managing it, based mainly on clinical attachment loss, radiographic bone loss, tooth loss attributed to periodontitis, and factors that complicate treatment.

Grade: how fast it is progressing

Grade A, B or C describes the rate of progression and the risk of future progression, using direct or indirect evidence of past progression and modifiers such as smoking and diabetes.

From classification to treatment

The European Federation of Periodontology’s S3-level clinical practice guideline, published in 2020, built a stepwise treatment approach for stage I–III periodontitis on this framework. Both papers, and the consensus report that introduced the classification, are in our library.

This article is for education. It is not a substitute for clinical assessment.