Sudden toothache in the elderly may be caused by pulpitis, many elderly people will have tooth decay, and most of the elderly teeth will have exposed roots, when the roots are exposed, root surface caries will easily appear in the roots, the progress of root surface caries is faster than ordinary caries, and it is easy to develop into pulpitis, causing sudden and severe pain. If periodontal disease occurs in the elderly, when the alveolar bone is absorbed to a certain degree, the length of the tooth root in the alveolar bone will be very short, and it is easy to induce retrograde pulpitis, which will cause severe pain to the hot and cold food suddenly, and some elderly teeth are gradually loosened, and severe pain will occur after biting into hard objects.