Abstract: The present disclosure provides a computer-implemented method for correlating at least one infrared 2D-image to a 3D-representation of at least a part of a tooth displayed in a graphical user-interface, of a hand-held scanning device, on a screen, including the steps of: obtaining a first set of 2D-images of the at least part of the tooth; forming a 3D-representation of the at least a part of the tooth from the first set of 2D-images; displaying, in the graphical user-interface, the 3D-representation; obtaining a second set of 2D-images, wherein the second set of 2D images are infrared 2D-images acquired within the at least part of the tooth; displaying, in the user-interface, at least one of the 2D-images from the second set of 2D-images; displaying, in the user-interface, a manipulator configured to change between 2D-images in the second set of 2D-images.