The invention relates to a process for determining the form a duplicate of a residual tooth area, which is to be fitted with a dental restoration whereby the duplicate sections to be fitted with the restoration are removed from the duplicate and the form data to be allocated to their forms has to be determined and stored in a computer, by means of which the form of the restoration is calculated taking into consideration the spatial allocation of the duplicate sections. In order to be able to determine the shape of the residual tooth area to be fitted with the restoration, and thereby determine the shape of the restoration itself with high precision, it is proposed that the duplicate sections are or are being individually referenced to each other in their spatial allocation to each other according to a referencing stored in the computer.