A scanning system for carrying out a 3D scan of a tooth model includes an imaging device and a positioning system in the form of a sliding panel which can be positioned and has first locking means. On the locking panel there are provided second locking means which interact with the first locking means such that the sliding panel can assume one of several specified positions relative to the locking panel and locks in the selected position. The sliding panel has means for mounting a dental model and stands on projections disposed on its underside. A 3D scan of a tooth model is provided by creating a first image of the object to be scanned at a precisely defined locked position, moving the sliding panel to at least one further precisely defined locked position and creating another image at each such position, and creating a 3D data set by evaluating the images produced at least two different, precisely defined positions.