Prognosis
With comprehensive treatment and SPT, Stage I–II: ~0.06–0.1 teeth lost/year. Stage III–IV: 0.3–0.5 teeth/year. Untreated: 1–3 teeth/year. Regular SPT reduces tooth loss by 90% vs. no maintenance.
Hopeless tooth criteria: advanced furcation Class III, CAL to apex, extreme crown-root ratio, root proximity preventing plaque control.