Disclosed is a method for planning, visualizing, and/or optimizing dental restoration on at least a part of the pre-prepared teeth of a patient, wherein said method include the steps of: providing at least one 3D digital model of at least a part of the pre-prepared teeth； designing at least one dental restoration CAD model based on the 3D digital model of at least a part of the pre-prepared teeth； providing at least one 3D digital model of at least a part of the prepared teeth, where the prepared teeth are provided by preparing the pre-prepared teeth by dental restorative work, at least partly based on the dental restoration CAD model； and aligning the 3D models of the pre-prepared and the prepared teeth.
