Neuropathic toothache generally refers to acute pulpitis, often manifested as hot and cold pain, spontaneous pain, night pain and other symptoms. 1. Hot and cold pain: after acute inflammation of the pulp, due to pulp infection, the pressure of the pulp cavity increases, and severe irritating pain occurs when encountering hot and cold food, with the development of inflammation, the pulp is gradually liquefied and decomposed, the cold stimulus is relieved, and the pain is aggravated when encountering heat, so that the patient has been holding cool water in his mouth. 2. Spontaneous pain: Inflammation of the pulp, liquefaction and exudation, resulting in increased pressure in the cavity, there can be severe spontaneous pain, the application of drugs can not be relieved, while the pain can not be localized, but also to the head of the radioactive pain. 3. Night pain: at night when resting, due to the position of the reason, the return of blood increased, increased pressure in the pulp cavity, the pain worsened at night when sleeping. Need to promptly seek medical attention, under the guidance of the doctor for treatment, to avoid delaying the condition .