Neuropathic toothache generally refers to pain caused by acute pulpitis, which is an acute inflammation of the pulp tissue caused by bacterial infection. The typical clinical symptoms of pain include spontaneous pain, paroxysmal pain, which often comes on suddenly and is intense, usually for several minutes. As the disease progresses, the attack period lengthens, the interval shortens, and gradually changes to persistent pain. The pain often comes on at night and is more pronounced when lying down, and can be secondary to or exacerbated by cold, heat, or acidic stimuli. If the pain is in the acute inflammatory and septic phase, it is obvious that the pain is hot and cold, and the pain cannot be localized.