The most common dental diseases include dental caries, pulpitis, apodontitis, periodontal disease, and the clinical manifestations and symptoms of each dental disease are different. I. Tooth decay, pain when stimulated by hot or cold or food embedment, and the pain disappears immediately after removing the stimulus. Pulpitis, persistent pain when stimulated by hot or cold, radiating pain in the ipsilateral ear and temporal area, spontaneous pain at night, and the pain cannot be localized. C. Apical tooth inflammation, a feeling of floating and swelling of the tooth, contact when biting, bite pain, bite weakness or percussion pain. Fourth, periodontal disease, alveolar bone resorption, gum recession, tooth movement and loosening, periodontal overflow pus are its main clinical manifestations. As the saying goes, toothache is not a disease, but pain really kills. All of the above conditions are painful when the disease attacks. Except for tooth decay, the treatment of other diseases is carried out under local anesthesia or nerve block anesthesia, and the treatment is basically painless or very mild and tolerable.