A.2mm B.3mm C.5mm D.7mm E.10mm
A.盡量長(zhǎng) B.達(dá)根長(zhǎng)的4/5 C.越長(zhǎng)固位越好 D.至少等于冠長(zhǎng) E.根尖部保留至少3mm根充物
A.0.5~0.9mm B.1.0~1.5mm C.1.6~1.9mm D.2.0~2.5mm E.2.6~3.0mm