The stages of periodontal (dental) disease
Stage 1: Early Gingivitis (gum disease). Changes here are reversible with dental treatment.
Stage 2: Early Periodontal Disease: Changes here are reversible with dental treatment.
Stage 3: Moderate Periodontal Disease: Changes here may be irreversible.
The bone that would hold the teeth in place has been eaten away by infection; teeth are now loose. This will require oral surgery to extract the affected teeth. In advanced cases, so much bone can be eroded that the jaw can break and require orthopedic plating or wiring for repair.
Stage 4: Severe Periodontal Disease.