The main reasons for itchy teeth are as follows: first, suffering from periodontitis, periodontitis is a chronic inflammation of the soft tissues around the teeth, it will lead to gum atrophy, alveolar bone resorption, red and swollen gums, brittle texture, easy bleeding, when the periodontal disease progresses to a certain degree, the teeth will have a feeling of swelling and itching, and there will be gradual loosening, no way to bite hard objects. Second, suffering from pulpitis or periapical inflammation, it is often due to trauma or decay on the tooth surface, without timely treatment, the infection has reached the pulp nerve, inducing pulp inflammation, which leads to long-term tooth pain and itching discomfort. If the pulp inflammation is not treated in time, the infected substance will spread to the periapical area along the apical foramen. When the tooth bites the substance, the pressure will stimulate the inflammatory area of the periapical area, resulting in painful itchy discomfort in the tooth.