The time of necrosis after dental nerve exenteration is affected by individual differences and the exact time cannot be specified. After the tooth nerve is exposed, it will cause more obvious pain, generally early pulpitis will appear more obvious spontaneous pain, night pain, radioactive pain and other typical symptoms, if not treated in time, the acute pulpitis will gradually become chronic pulpitis, at this time the pain symptoms are not so obvious, if the chronic pulpitis is still not treated, the tooth nerve will gradually necrosis, become dead pulp teeth, the patient at this time generally There is no obvious discomfort. However, it is important to note that this process is not an improvement, but rather an increasingly severe lesion, and that the pulpal tooth may continue to develop into a periapical infection. There are individual differences in the process and there is no exact time when the nerve dies. It is recommended to seek medical treatment as soon as possible after the tooth leaks a nerve, and not to delay it for fear of pain, which leads to worse and worse and may end up not being retained and needing to be extracted.