Patient: Main symptoms, onset time: pain, one week ago Examination time, content: this Sunday The last big tooth on the lower right side was filled 7 years ago, and two months ago a small piece of tooth was lost on the last side of the tooth near the flesh, and then the pain, one month ago in XX Hospital after 3 weeks of drug observation will be filled with the lost part, and after filling, biting hard things, I still feel afraid to force. After the filling, I still feel afraid to bite hard things, but it doesn’t hurt when I don’t use it. A week ago, it suddenly became painful, even when not in use. Today, the examination said that the nerve was inflamed and root canal treatment was needed. The doctor drilled out the original filling material, used a long thin needle to pick the nerve in the tooth (the process is very slow and painful), then took a dental film, then continued to pick, then took a second dental film, then used a 2-3 cm long iron needle to drill inside, then applied medicine and said that I should pass 3-5 days later. 1. Is the nerve already picked out? 2. What else do I need to do for the next treatment? 3. what are the potential dangers of the following treatment, and will it still be painful? Yang Yang, Department of Stomatology, Beijing 301 Hospital, Beijing: 1. According to your description, the treatment done by the doctor should be pulp extraction and root canal preparation. If there is inflammation in the pulp, the nerve will not be shaped, it is possible that the extraction is not clean at one time, and there may be pain at the next follow-up is normal. As the treatment continues, after the root canal preparation is completed, the root canal will be cleaned. 2, the next treatment: if your last treatment root canal preparation once in place, no symptoms can be root canal filling; if your last treatment is only the first preparation of root canal, then the next will have to continue to prepare the root canal, and wait until the next follow-up to do root canal filling. 3, for the third point of your consultation, you can go to the article of my consultation guide [filling, root canal treatment patient information] in article 7 and 10, the above is very clear.