Screw channel insertion piece for forming the casting mould of the screw channel of the frame supporting a dental device. The insertion piece (2) comprises a base body (9) fixed to the analogue implant(s) (8) by means of a screw (6) via an interface (5), an internal section (10) mounted on the base body (9) and a terminating ring (11) each of which is provided with a bore-hole in their centre point. The internal section (10) comprises ball-shaped rings (12) fitted in or fitted on each other. The ball-shaped rings (12) and the terminating ring (11) are cylindrically symmetric elements having a surface forming an essentially spherical segment at least at their fitting portion. Further, the ball-shaped rings (12) and the terminating ring (11) are fitted into each other in a curve so that when the dental device (3) is finished the hole of the screw channel (1) at its end opposite the analogue implant (8) faces the oral cavity.
