When a tooth is knocked out of the vertical lines, cracks in the enamel are usually present. Observation, veneer repair, root canal treatment and other treatment measures should be taken according to the size and depth of the cracks. 1. Observation: If the range of vertical lines on the crown is not long and the depth is only in the enamel layer, and there is no special clinical discomfort, observation can be carried out. Local attention should be paid to avoid eating too cold and too hot stimulating food, not eating hard objects, maintaining oral hygiene, preventing plaque buildup, and preventing re-traumatization of teeth. 2. Veneer repair: If the crown of the vertical lines of a longer range and depth of wave and dentin layer, sensitivity symptoms and affect the aesthetic, desensitization treatment can be done after all-porcelain veneer repair to restore the shape of the crown. 3. Root canal treatment: If the crown of the longer range of vertical lines and deeper, has affected the dentin layer or near the pulp, nerve pain and other uncomfortable symptoms, the teeth after root canal treatment, crown restoration treatment. The tooth was hit out of the vertical lines, should be timely consultation, improve the examination, under the guidance of a professional physician to carry out standardized treatment, in order to avoid delaying the condition.