A filling after root canal treatment is a filling of the pulp cavity and crown defect that has not been cemented with a filling material and restoration of the shape. The tooth is observed for a week after root canal treatment, if there is no pain or discomfort the filling can be placed, if symptoms are manifested then treatment should be continued. To fill a tooth after root canal treatment, it is necessary to use zinc oxide cushion to close the root canal opening, and then use glass ionomer cushion to cover the zinc oxide material, after the glass ionomer has solidified, then the wall of the tooth will be acid-etched, coated with adhesive, filled with resin material, and the shape will be restored. There is also the option of restoring by filling only with glass ionomer material. After the treatment of the teeth due to the lack of nerve nutrient supply, it is recommended to carry out inlay restoration or full crown restoration, the dentin defect is small recommended inlay restoration, the defect is large choose crown restoration, to prevent the teeth from splitting after treatment.