林××,女,39岁。因右上磨牙轻度疼痛10天,于1984年3月8日就诊。7|10年前曾作过“干髓治疗”,一直无异常。检查见76银汞合金充填,6|活力测验稍迟钝,|7无活力,叩痛(±)拟诊为7|慢性根尖周炎。经去除7|原充物,常规作根管预备,置入甲醛甲酚棉球于根管口,氧化锌丁香油糊剂暂封,封药时即感胀痛不适,一小时后 Lin × ×, female, 39 years old. Due to the right upper molars mild pain for 10 days, on March 8, 1984 treatment. 7 | 10 years ago had “dry marrow treatment” has been no exception. Check see 76 silver amalgam fill, 6 | vitality test a little dull, | 7 no vitality, percussion pain (±) to be diagnosed as 7 | chronic apical periodontitis. After the removal of 7 | original filling, routine for root canal preparation, placing cresol cotton balls in the root canal mouth, zinc oxide clove oil paste temporary seal, that is, when the flu pain and discomfort, one hour later