Except for individual teeth with few defects and small occlusal forces, most teeth after root canal treatment are often recommended by dentists to undergo “crown restoration” after root canal treatment in order to better exercise the occlusal function, prevent tooth splitting and prolong tooth life or for aesthetic reasons. If we compare dental treatment to a house, “root canal treatment” is the invisible but critical “foundation” work below, while “crown restoration” is the “house” repair work above. The “crown restoration” is the repair work of the “house” above. Depending on the amount of healthy tissue remaining in the tooth and different oral conditions, the doctor will recommend different restorative methods. These include inlays, full crowns or pile crown restorations. From a minimally invasive point of view, the “inlay” method is the best choice among the three restorative methods, as it allows for more preservation of healthy tooth tissue. However, the latter two methods are often recommended when there are hidden cracks in the tooth or when the amount of remaining teeth is small. Of course, the treatment method varies from person to person depending on the oral condition, and the doctor needs to weigh and consult with the patient to decide.