The dental examination includes: 1.Temperature test of pulp vitality, including cold diagnosis method and hot diagnosis method, when the pulp has lesions will be sensitive or dull to cold or hot stimulation, or even no response. 2.Electrical test of pulp vitality, by testing the response of nerve fibers in the pulp to electrical stimulation, to help determine the state of the pulp. 3.Place a small cotton ball or small toothpick on the site of occult fracture, and ask the patient to chew, if it is obvious that the pain is deep. If the pain is obvious, it means that the occlusion is deeper.4. Apply 2% tincture of iodine or 1% methyl violet solution on the surface of the tooth, and the deeper stained fold is the site of occlusion.5. Use the light source of the optical fiber illuminator to illuminate the tooth replacement to check the internal structure of the tooth and assist in clinical diagnosis.6. Take oral radiographs, full-mouth surface tomography and oral CT, which are effective auxiliary examinations.