Crowns are recommended for incisors that have undergone root canal treatment, which have the main advantages of maintaining aesthetics, improving the success rate of root canal treatment, and fracturing the tooth. 1. Maintaining aesthetics: some incisors will be discolored after root canal treatment. Crowns are aesthetically pleasing. 2. Improve the success rate of root canal treatment: the crown can protect the filling and tooth tissue from micro-leakage, greatly improving the success rate of root canal treatment. 3. Tooth fracture: some incisors have too much tooth loss, coupled with the increased brittleness after root canal treatment, there is a risk of fracture, crowns can play a protective role. It is recommended to go to a regular hospital stomatology consultation, listen to professional advice, according to the oral cavity, assess the risk.