2017 World Workshop on the Classification of Periodontal and Peri-implant Diseases and Conditions

This new classification has superseded older classifications. However, it may be wise to remain familiar with the older classification categories. The health of the patient’s periodontium may be assessed directly, from visible gingival inflammation (changes in appearance) and levels of plaque and calculus buildup. In health, the level of the free gingival margin should rest about 2-3mm coronal to the cemento-enamel junction (CEJ), and the epithelial attachment is found at or immediately adjacent to the CEJ. In health, the alveolar bone crest lies 1-2mm below the level of the CEJ. The distance between the start of the epithelial attachment and the crest of the alveolar bone is known as the biological width. The new periodontal classification system is broken down as the following:

1 – Necrotizing Periodontal Diseases. 

• • Necrotizing Gingivitis.
  • Necrotizing Periodontitis.
  • Necrotizing Stomatitis.

2 – Periodontitis as Manifestation of Systemic Diseases.

3 – Periodontitis.

• • STAGE – based on the severity and extent of distribution, as well as the complexity of management. “Stage” is a snapshot in time. Severity is primarily based on the interdental clinical attachment loss (CAL) at the worst site. Complexity is primarily based on additional local factors (furcation involvement, trauma, bite collapse etc.). 

• • • Stage I – Initial periodontitis
      • 1-2mm CAL
      • ≤4mm probing depth
      • mostly horizontal bone loss
      • no teeth lost

• • • Stage II – Moderate periodontitis
      • 3-4mm CAL
      • ≤5mm probing depth
      • mostly horizontal bone loss
      • no teeth lost

• • • Stage III – Severe periodontitis with the potential for additional tooth loss
      • +5mm CAL
      • ≥6mm probing depth
      • ≥3mm vertical bone loss
      • furcation involvement Class II or greater
      • ≤4 teeth lost

• • • Stage IV – Severe periodontitis with the potential for loss of the dentition
      • +5mm CAL
      • ≥6mm probing depth
      • ≥3mm vertical bone loss
      • furcation involvement Class II or greater
      • Occlusal trauma
      • Occlusal collapse, drifting, or flaring
      • ≥5 teeth lost, or ≤20 teeth remaining 

• EXTENT (distribution). 

• • Localized – less than 30% of remaining teeth affected.
  • Generalized – more than 30% or remaining teeth affected.
  • Molar-incisor distribution.

• GRADE – determined by the rate of progression, responsiveness to treatment, and the assessment of risk. Unlike staging, the grade is a dynamic measurement of how things are changing over time. 

• • Grade A – Slow rate of progression. 

• • • No CAL in the past 5 years
    • %RBL/Age – less than 0.25
    • Minimal bone loss despite plaque buildup
    • Non-smoker
    • No diabetes
    • C-reactive protein less than 1mg/L

• • Grade B – Moderate rate of progression. 

• • • ≤2mm CAL in the past 5 years
    • %RBL/Age – between 0.25 and 1.0
    • Bone loss consistent with plaque buildup
    • Smoker (less than 10 cigarettes per day)
    • Well controlled diabetes
    • C-reactive protein 1-3mg/L

• • Grade C – Rapid rate of progression. 

• • • ≥2mm CAL in the past 5 years
    • %RBL/Age – more than 1.0
    • Excessive bone loss in light of plaque buildup
    • Smoker (more than 10 cigarettes per day)
    • Poorly controlled diabetes
    • C-reactive protein more than 3mg/L