Function: Anchorage, usually used on molars
It consists of a horizontal part and two U-shaped loops that merge from the transversal clasp parts to the retention. The clinical crown determines the height of the loops. These loops should have such height that the horizontal part of the clasp runs 1 – 2 mm below the cusps.
The bridge portion of the clasp should keep a distance of approximately 1 mm to the buccal surface of the tooth so that the clasp can be activated.Seen from occlusal, the angle between the loops, the bridge portion and the transversal part is approximately 45°. Therefore the loops find retention in the undercuts of the crown in the transition from buccal to interproximal.
Function: Improved retention in comparison to the original Adams clasp
Depending on the tooth width, a 9 cm long wire is marked parting from the middle at precisely 3.5 mm to the left and to the right so that a 7 mm long piece is marked in the centre of the wire. This part forms the buccal bridge portion between the two loops. The square part of the angle wire bending pliers is positioned from the inside at the markings and the wire is bent downward slightly over 90°.
Now two marks are made on the vertical parts, each 0.3 mm from the buccal bridge portion including the wire diameter. With the round tip of the pliers, the wire is bent upward by 180° at the markings on both sides.
Holding the pliers horizontally, the mesial loop is bent 75° to the bridge. The corresponding angles for the distal loop are 60° for the upper and 55° for the lower jaw.
The square part of the angle wire bending pliers (for example Dentaurum REF 004-139-00) is positioned 2 mm mesially and distally of the curve of the loop and the wire is bent lingually 90° to the axis of the loop.
According to the central groove, the transversal tag can be bent gingivally in a V-shape to avoid occlusal interferences.
A small V-shaped bend towards the gingival tissue at the central groove of the molar can be adapted to minimize occlusal interferences.
At the level of the lingual cusps the wire is bent around the square part of the angle wire bending pliers (for example Dentaurum REF 004-139-00) 60° towards the gingival tissue. Now both wire ends run parallel to the buccal axis of the loop.
According to the crown length, the wire is bent afterwards 60° from the marginal gum. Now the wire end runs parallel to the occlusal surface. Directly after this bend, the tag is bent again gingivally, parallel to the gingival tissue in a distance of 1 – 2 mm.
Afterwards, the two wire ends are bent to form the retention.
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