A.2.5mm B.3mm C.不小于1mm D.3.5mm E.2mm
A.1/3~1/2 B.2/3~3/4 C.1/2~3/4 D.1/3~3/4 E.與樁冠的冠部等長(zhǎng)即可
A.0.5~2.5mm B.1~3mm C.不小于4mm D.3~5mm E.5~7mm