Reports & Studies

New classification scheme for periodontal diseases

Prof. Dr. Peter Hahner

In June 2018, as part of the EuroPerio 9 conference in Amsterdam, the long-awaited new classification scheme for periodontal and peri-implant diseases was presented publicly to dentists.

The aim of the new classification is to incorporate new findings about periodontal diseases (particularly regarding their aetiology and pathogenesis) that have been made since the 1999 International Workshop for a Classification of Periodontal Diseases and Conditions (Armitage,1999), and to include peri-implant diseases for the first time. In addition to several clarifications and necessary adaptations to terminology (for example, to the diagnostic codes of the ICD [= International Statistical Classification of Diseases and Related Health Problems]), the classification includes the following changes relevant to dentists’ daily work in periodontal prevention, active non-surgical treatment and the maintenance phase:

Introduction of the term ‘clinical periodontal health’. Previously, health in periodontology was more or less understood as the absence of disease. However, there now exists a precise description of a healthy periodontal condition, both in patients who have not yet been affected by periodontal disease and in those who have successfully completed periodontitis treatment.
The definition of gingivitis as a non-specific inflamed lesion that manifests only in the area of the gingivae and does not affect the root cementum, periodontal ligament and alveolar bone, has also been reclassified as a disease in patients with a still-intact periodontium and in patients who have been successfully treated for periodontitis.
The previous distinction between chronic and aggressive periodontitis has been dropped. This is because the last few years have shown that the differences between the two (e.g. the assumption that they differ with regard to pathogen spectrum) increasingly cannot be clearly classified. Instead of this division, a classification based on the degree of severity (staging, stages I–IV) and anticipated progression of disease (grade A–C) has been introduced. Based on this distinction, concrete conclusions can be made regarding required therapeutic interventions, the difficulty of treatment and possible complications.
Peri-implant diseases and conditions are included in this classification for the first time.

At first glance, a classification system might seem like very dry material for discussion, and might appear to be of more relevance for epidemiological studies. However, closer inspection of the classification reveals useful applications for everyday clinical practice. Ultimately, a classification is the matrix that enables us to combine the patient’s medical history and clinical and radiological findings into the most highly tailored and individual diagnosis possible. In turn, this individualized diagnosis is the prerequisite for providing every patient with personalized treatment, a concept that is increasingly in demand.

After this introduction, the individual changes in this classification will gradually be examined in more detail in the coming weeks.


  1. Albandar, J. M., Susin, C., & Hughes, F. J. (2018). Manifestations of systemic diseases and conditions that affect the periodontal attachment apparatus: case definitions and diagnostic considerations. Journal of clinical periodontology, 45, S171-S189.ld
  2. Caton, J., Armitage, G., Berglundh, T., Chapple, I. L., Jepsen, S., S. Kornman, K., ... & S. Tonetti, M. (2018). A new classification scheme for periodontal and peri‐implant diseases and conditions – Introduction and key changes from the 1999 classification. Journal of periodontology, 89, S1-S8.