This fact is from 2017 Periodontal Classification in Periodontology. It is a commonly tested concept in NEET MDS examinations. Understanding this fact is crucial for answering MCQs correctly.
Stage II moderate = 3-4mm CAL
Stage III severe = 5mm+ CAL
Stage IV very severe = extensive tooth loss
Grade A slow = no evidence of progression
Grade B moderate = matches disease
Grade C rapid = exceeds expectations risk factors smoking diabetes
Replaces aggressive and chronic periodontitis terminology.