No pain during the day and pain at night after tooth extraction may be related to vagus nerve excitation, pulpitis of neighboring teeth, and the effect of anesthesia. 1. Vagus nerve excitation at night: night pain is mainly due to the daytime energy or attention is focused on work or life, not deliberately pay attention to the wound pain. At night in a quiet state, the vagus nerve excitation, increased sensitivity to pain, will over magnify the pain of the wound. 2. Pulpitis of neighboring teeth: it may be caused by the pulpitis of neighboring teeth when growing wisdom teeth, and pulpitis pain often occurs at night, or the pain at night is more intense than during the day. 3. Anesthetic effect: the dose of anesthetic for tooth extraction is related to the growth of the tooth, and may be injected with a larger dose. Or part of the population anesthetic metabolism is slow, there will be no pain during the day after tooth extraction night pain. After the extraction of daytime pain at night pain can also be seen in other reasons, it is recommended to consult a doctor in a timely manner, in accordance with the doctor’s instructions for the relevant examination, in the doctor’s help to clarify the cause, and targeted treatment or treatment.