In the clinic, many patients and friends go to fill the teeth, there is no discomfort when they go, but there is a lot of discomfort after filling, for this reason many patients do not understand, now I explain it in detail, hope it will be helpful to the patients and friends: Because the deep caries is deeper and closer to the dental nerve, generally adopt conservative treatment as far as possible, keep the nerve as far as possible, and soothe or fill as appropriate depending on the situation. If there is no discomfort after the deep caries is pacified, generally come back again after one month for permanent filling, but it is possible to kill the nerve in the future after coming back for filling, because the caries is too deep and too close to the nerve, stimulating the nerve, and the nerve is inflamed, so it needs to do root canal treatment. 2.After the deep caries is pacified, it may be uncomfortable to go back, hot and cold, but gradually reduce, one month basically no discomfort, also can come back to the dentist to fill again, but after coming back to fill may also need to kill the nerve in the future, because the bad is too deep and too close to the nerve, stimulate the nerve, the nerve inflammation, need to do root canal treatment. 3.After the deep caries filling, it is very uncomfortable to go back, there is hot and cold pain, spontaneous pain, night pain, and there is no sign of improvement, it is necessary to come back to kill the nerve and do root canal treatment in time, because the bad is too deep, the nerve is inflamed, and the nerve can’t be preserved. After deep caries filling, if there is no discomfort and no discomfort, the treatment will be finished for the time being, but there is a possibility that chronic inflammation will occur in the future, resulting in inflammation of the nerve, and root canal treatment is needed. 2.After deep caries filling, some of them will have hot and cold sensitivity in the short term, but the symptoms will gradually subside and disappear with time, so the treatment will be finished for the time being, but there is a possibility that chronic inflammation will occur in the future, leading to inflammation of dental nerve and root canal treatment is needed. 3.After deep caries filling, there is no discomfort at that time after deep caries cavity filling and soothing, but spontaneous pain, hot and cold pain, night pain appears a few days after filling, maybe the nerve of the tooth is inflamed, need to do root canal treatment. 4.After the deep caries filling, the cavity preparation process, because the caries is too big, the tooth nerve leakage, then need to perform root canal treatment. Warm tip: In order to reduce the discomfort, avoid eating too cold and too hot food after filling. If the pain is not relieved or spontaneous pain occurs, please contact with the doctor in time.