成年人上前牙外伤，冠折1/3，露髓，根正常。其治疗原则为
A．活髓切断术
B．直接盖髓
C．干髓术
D．根管治疗
E．塑化治疗
参考答案：D
—I want to know when ______have a break.
—We'll go out for a walk when the work______.[ ]
A. will you; will finish
B. will you; finishes
C. you will; is finished
D. you will; finishes
表观密度
