用刚拔出的磨牙40个,均无龋损、无融合根。实验组30个牙,揭髓盖后,在髓底造成穿孔,随机均分为3组,分别用汞合金,Cavit和光固化玻璃离子粘固粉修补穿孔,用光固化复合树脂充填窝洞。对照组10个牙,随机均分为两组:造成穿孔不作处理作阳性对照和只涂布指甲油作阴性对照。将所有牙齿浸入2％红霉素B染料中1周,测量穿孔区染料浸入的深度,以比较3种 With just pulling out the molar 40, no carious lesions, no fusion root. The experimental group of 30 teeth, after exposing the pulp cover, punctured the bottom of the pulp, were randomly divided into three groups, respectively, with amalgam, Cavit and light-cured glass ionomer powder repair perforation, light curing composite resin filled cavity. Ten teeth in the control group were randomly divided into two groups: no perforation was made as a positive control, and only nail polish was applied as a negative control. All teeth were immersed in 2% erythromycin B dye for 1 week, and the depth of dye penetration in the perforated zone was measured to compare three