Occlusal rests, TPA and lingual bow 1 mm hard or one piece casting method
Function:
Achievement of a neutral occlusion after tooth eruption is finished
Description:
In order to avoid a transversal movement of the anchorage teeth, the rigid construction of the Herbst® appliance is chosen
The preformed crowns are adapted and big perforations are made in the middle of the occlusal surfaces in order to allow the cement to flow and to make the removal of the bands after treatment easier. In the upper jaw, the TPA and the occlusal rests can be bent out of one piece of wire and then be soldered. In the lower jaw, the occlusal rests are soldered separately on the premolars and the lingual arch is soldered to the crowns.
The buccally located guiding hinges (for anchorage reasons) are assembled and screwed. The length of the guiding hinge has to be checked in the mounted casts which are set into the fixator by a construction bite.
In the Herbst® appliance, made with the one piece casting method, the attachments for the anchorage of the guiding telescopes are soldered. In this construction, the TPA in the upper jaw is not absolutely necessary.
