An impression system includes an impression cap (4) for transferring an end, protruding from a human tissue structure, of an implant (1) which is fitted in the human body, including possible superstructures, to a master cast. The outwardly directed implant end has an undercut contour on its outside, and the impression cap (4) has a geometry which complements the undercut contour and engages therein. The undercut contour is formed either by an implant geometry tapering in a trumpet shape towards the implant bed, or by a recess near the implant end. Taking an impression and producing a master cast are greatly simplified with the impression system. In addition, the actual geometrical situation on the patient can be transferred to the master cast with greater precision.