Class 2 and Class 3 furcation — all can be part of treatment plan EXCEPT:

For Class 2 and Class 3 furcation involvement treatment options: Tunnel preparation (B — for class III mandibular molars), Odontoplasty/furcationplasty (C — for class II, converting to class I), Extraction + implant (D — if tooth not saveable), Hemisection/root resection (E — class II/III). GTR (A) is effective for CLASS II furcations (especially mandibular) but has LIMITED success for CLASS III furcations (through-and-through), where it is generally NOT indicated. For the combined 'class 2 AND 3' question, GTR is least applicable. A is the EXCEPT.