When a tooth inside a porcelain tooth hurts, an oral x-ray will be taken and treatment will be based on the specific situation. If secondary caries occurs in the abutment teeth, sensitivity to stimuli such as hot, cold, sour and sweet need to remove the porcelain crowns, thoroughly remove the decayed tooth tissue, and then try on a temporary crown. After the symptoms are alleviated, the porcelain crown will be remade and cemented in place. If the X-ray shows that the teeth inside the pulpitis or periapical inflammation occurs, you can grind in the center of the jaw of the porcelain crown, to reach the pulp cavity, remove the infected pulp, after the pain is reduced, to complete the root canal preparation, root canal filling and so on. Finally, composite resin is used to close the cavity and restore chewing function.