A.0°~2° B.2°~5° C.5°~10° D.10°~15° E.對(duì)聚合角度無(wú)要求
A.牙體長(zhǎng)度的1/2~1/3 B.牙根長(zhǎng)度的1/2~1/3 C.牙體長(zhǎng)度的2/3~3/4 D.牙根長(zhǎng)度的2/3~3/4 E.都不正確