Bad incisor black is mostly caused by dental caries, you need to go to the hospital in time to clean up the decayed and necrotic dental tissues, not through the pulp cavity resin filling, through the pulp cavity need to be filled after root canal treatment. 1. Unpenetrated pulp cavity: If the incisor is broken and the caries has not penetrated the pulp cavity, it is necessary to use special instruments to remove the decayed and necrotic tooth tissues, and then fill the cavity with resin according to the depth of the cavity or fill the cavity with resin after medication cushioning, and then repair the defect with veneer or crown when the defect is larger in scope. 2. Through the pulp cavity: If the caries has penetrated deep into the pulp cavity, the pulp tissue has been infected, need to carry out root canal treatment, root canal treatment, consider crown restoration. It is recommended to go to the hospital as soon as possible to check and deal with the caries to avoid the progress of caries causing more serious consequences.