The assignment of the mandible to the maxilla and thus the occlusal relationship in the virtual treatment simulation was previously performed exclusively in centric occlusion by means of a buccal scan. When the tooth position is changed in the virtual treatment simulation, the assignment of the mandible to the new occlusion is made by means of “best fit”, a pure vertical elevation of the mandible that differs from the closing and opening movement of the mandible in real motion according to the global centre of rotation, formerly known as the hinge axis.