Electronic unit implemented method for generating dental data suitable for manufacturing of a dental aligner, comprising the steps of: A) storing a 3D scan of an impression of a dental arch or of a reproduction of a dental arch or of an original of a dental arch, obtaining scan data of said dental arch, B) for each tooth of a dental hemiarch of said dental arch, calculate position of a node, width, inclination of a disto-mesial axis, inclination of a root axis, and inclination of a linguo-buccal axis starting from said scan data, C) selecting at least one node, preferably at least two nodes, according to the calculation of step B, D) determining a curve in an occlusal plane passing through said at least one node or for said at least two nodes and preferably for a central point of a dental interstitium between two central incisal teeth of said dental arch, E) determining a positioning of the tooth nodes of said dental hemiarch in particular on said curve, in which said positioning derives, for each tooth of said hemiarch, from a combination of a tooth translation and a tooth rotation around to the root axis, where said positioning takes into account the width of the teeth, F) determining an elevation of the nodes of the teeth of said dental hemiarch, wherein said elevation derives, for each tooth of said hemiarch, from a translation of the tooth such that the tooth node is on a sphere of Monson, and G) determining an orientation of the teeth of said dental hemiarch, wherein said orientation derives, for each tooth of said hemiarch, from a rotation of the tooth such that the TIP angle and the TORQUE angle of the tooth correspond at predetermined angle values; whereby said dental data are calculated on the basis of said scan data as well as the positioning determined in step E, the elevation determined in step F, the orientation determined in step G. A) storing a 3D scan of an impression of a dental arch or of a reproduction of a dental arch or of an original of a dental arch, obtaining scan data of said dental arch, B) for each tooth of a dental hemiarch of said dental arch, calculate position of a node, width, inclination of a disto-mesial axis, inclination of a root axis, and inclination of a linguo-buccal axis starting from said scan data, C) selecting at least one node, preferably at least two nodes, according to the calculation of step B, D) determining a curve in an occlusal plane passing through said at least one node or for said at least two nodes and preferably for a central point of a dental interstitium between two central incisal teeth of said dental arch, E) determining a positioning of the tooth nodes of said dental hemiarch in particular on said curve, in which said positioning derives, for each tooth of said hemiarch, from a combination of a tooth translation and a tooth rotation around to the root axis, where said positioning takes into account the width of the teeth, F) determining an elevation of the nodes of the teeth of said dental hemiarch, wherein said elevation derives, for each tooth of said hemiarch, from a translation of the tooth such that the tooth node is on a sphere of Monson, and G) determining an orientation of the teeth of said dental hemiarch, wherein said orientation derives, for each tooth of said hemiarch, from a rotation of the tooth such that the TIP angle and the TORQUE angle of the tooth correspond at predetermined angle values;