拔牙后通常牙槽嵴吸收致上牙槽嵴變小而下牙槽嵴變大,有時需要排成反;當(dāng)無牙頜上下牙槽嵴頂連線與平面交角小于多少度時建議排反()
A.70 B.80 C.90 D.75 E.95
A.0° B.10° C.20° D.25° E.30°