water and sand of sprayer

AIM:To evaluate the effects of different ac id etching time on dentin surface tissue after prepared with air abrasion.

方法 :空气喷砂机对龋坏牙本质制洞后 ,对牙本质界面进行不同时间酸蚀 ,扫描电镜下观察牙本质界面的组织学变化。