The reproducibility of the positional relationship of mandible models in the Dentatus Articulator was studied. Based on the method of A.G. Lauritzen, the articulator is oriented on a hinge axis. The registration procedure was carried out by two subjects on three patients (5 times each). The deviations in the hinge axis point against a value of zero (initial measurement) were then determined with a face-bow. TMJ and SAM face-bows were used for these controls. The deviations from the mean value of the hinge axis point determined in the articulator were within the range of +/- 3 mm in the sagittal and vertical directions. The results tend to indicate that experience, routine, and knowledge of the varioius possibilities of error are necessary if the registration is to be accurate.