A.發(fā)育異常 B.根尖周囊腫 C.根尖周肉芽腫 D.慢性根尖周膿腫 E.根尖孔未形成
A.0.4~0.5mm B.0.4~0.55mm C.0.55~0.6mm D.0.62~0.75mm E.0.7~0.8mm