My experience

半年前一个牙齿的牙床肿了有一小包。二格月前看牙医说这个牙以前做过root canal.可我跟本没印象。肿是因为以前没有清理干净，root canal 需要重做，给我推荐了specialist. 普通的牙医做不了。 X-ray also shows 有一很小的缝隙在牙根处，周边有一园行状感染的牙床。牙医没说那是裂缝。我估计做root canal 是那里应当填上filling material。 Specialist gave me two options: 1) remove it, and 2)treat it.我选择了治。就是把旧的filling material 去掉，放药进去把细菌杀死。然后seal the hole using temporary filling material.三个星期过去了效果很好，肿以经全部消失了。I have another appointment next week to remove temporary filling material. I guess the speciallist will add more medicine inside and the seal the hole with permanent filling material. Good luck.