Reports & Studies

Classification of gingivitis

Prof. Dr. Peter Hahner

The new classification continues to differentiate between plaque-induced gingivitis and non-plaque-induced gingival diseases (Chapple et al., 2018). As before, plaque-induced gingivitis is defined as a non-specific inflammatory lesion that results from a limited immunological response to an increased accumulation of biofilm on the gingival margin and in the gingival sulcus, which only manifests in the area of the gingivae. There is no involvement of the cementum, periodontal ligament or alveolar bone (Murakami et al., 2018). The clinical signs are swelling, reddening and, in some circumstances, a certain degree of tenderness. Instead of the usually commonly used gingival index (GI) (Löe, 1967), the bleeding on probing (BoP) index was selected as the diagnostic criterion for distinguishing between clinical periodontal health and gingivitis for the current classification. In the BoP index, bleeding is stimulated by applying light pressure (corresponding to a load of ≤ 25 g) to the base of the gingival sulcus or periodontal pocket. The BoP index is regarded as the standard parameter for monitoring inflammatory activity in the maintenance phase of systematic periodontitis treatment; thus, there were practical reasons for standardizing diagnostics.

Similar to the description of the state of clinical periodontal health, a distinction continues to be made between a site- or tooth-specific diagnosis of gingivitis and a diagnosis on the level of the patient (Trombelli et al., 2018).

Localized gingivitis is present if more than 10% and no more than 30% of measurement sites are positive for bleeding on probing (BoP+). If more than 30% of sites are positive for bleeding on probing, this is referred to as generalized gingivitis. In principle, pocket probing depths may be no more than 3 mm (Table 1).

As for clinical periodontal health, a distinction continues to be made between gingivitis in an intact periodontium and gingivitis in a reduced periodontium (Tables 2 + 3).

The new classification therefore enables a highly differentiated description of periodontal conditions: first of all, a patient can develop fully reversible gingivitis from a state of periodontal health. Periodontitis with loss of attachment can develop at the base of this gingivitis. The periodontally healthy patient has then become a ‘periodontitis patient’, via the intermediate stage of ‘gingivitis patient’. Depending on the success or failure of periodontal treatment, the periodontitis patient will achieve a state of periodontal health (= stable case) or a state of sites of gingival inflammation (= ‘gingivitis in reduced periodontium’), or the patient will remain a periodontitis patient (= unstable case with recurrent flare-ups of disease) (Chapple et al., 2018).


  1. Chapple, I. L., Mealey, B. L., Van Dyke, T. E., Bartold, P. M., Dommisch, H., Eickholz, P., ... & Griffin, T. J. (2018). Periodontal health and gingival diseases and conditions on an intact and a reduced periodontium: Consensus report of workgroup 1 of the 2017 World Workshop on the Classification of Periodontal and Peri‐Implant Diseases and Conditions. Journal of clinical periodontology, 45, S68-S77.
  2. Murakami, S., Mealey, B. L., Mariotti, A., & Chapple, I. L. (2018). Dental plaque–induced gingival conditions. Journal of clinical periodontology, 45, S17-S27.
  3. Löe, H. (1967). The gingival index, the plaque index and the retention index systems. The Journal of Periodontology, 38(6P2), 610-616.
  4. Trombelli, L., Farina, R., Silva, C. O., & Tatakis, D. N. (2018). Plaque‐induced gingivitis: Case definition and diagnostic considerations. Journal of clinical periodontology, 45, S44-S67.