目的比较两种根管预备方法对根管约诊间痛的影响。方法将134例急、慢性牙髓炎或根尖周炎的152颗前磨牙采用随机原则分为观察组(T组......

A novel n-type junctionless field-effect transistor(JLFET)with a step-gate-oxide(SGO)structure is proposed to suppress t......