A computer implemented method for digitally designing a modified dental setup on a digital 3D dental model representing at least a part of the teeth of a patient comprising the steps of: - loading, from a data source, a pre-treatment digital 2D image of at least a part of the teeth of the patient; - loading, from a data source or via scanning, a digital 3D representation of the at least a part of the teeth of the patient; - obtaining a proposed digital 2D image of a desired dental setup by digitally creating, through user interaction, at least one digital tooth modification based on the pre-treatment digital 2D image; characterized by - determining a transformation by estimating a camera view for the pre-treatment digital 2D image based on a correlation of at least one facial feature in the pre-treatment digital 2D image and corresponding at least one facial feature in the digital 3D representation, wherein determining the transformation based on the correlation comprises identifying corresponding points of at least one facial feature in the pre-treatment digital 2D image and corresponding at least one facial feature in the digital 3D representation, and the at least one facial feature comprises at least a part of one or more of the teeth visible in the digital pre-treatment 2D image and represented in the digital 3D representation; and - transferring the at least one digital tooth modification from the proposed digital 2D image to the digital 3D representation according to the transformation. - loading, from a data source, a pre-treatment digital 2D image of at least a part of the teeth of the patient; - loading, from a data source or via scanning, a digital 3D representation of the at least a part of the teeth of the patient; - obtaining a proposed digital 2D image of a desired dental setup by digitally creating, through user interaction, at least one digital tooth modification based on the pre-treatment digital 2D image; characterized by - determining a transformation by estimating a camera view for the pre-treatment digital 2D image based on a correlation of at least one facial feature in the pre-treatment digital 2D image and corresponding at least one facial feature in the digital 3D representation, wherein determining the transformation based on the correlation comprises identifying corresponding points of at least one facial feature in the pre-treatment digital 2D image and corresponding at least one facial feature in the digital 3D representation, and the at least one facial feature comprises at least a part of one or more of the teeth visible in the digital pre-treatment 2D image and represented in the digital 3D representation; and determining the transformation based on the correlation comprises identifying corresponding points of at least one facial feature in the pre-treatment digital 2D image and corresponding at least one facial feature in the digital 3D representation, and the at least one facial feature comprises at least a part of one or more of the teeth visible in the digital pre-treatment 2D image and represented in the digital 3D representation; and - transferring the at least one digital tooth modification from the proposed digital 2D image to the digital 3D representation according to the transformation.