Class II Jig
Intermaxillary elastics are a popular aid when treating Class II cases. Experienced orthodontists are aware, however, that their use can occasionally lead to undesired side effects. They often result in extrusion of the anchoring teeth, steepness of the maxillary canines or inclination of the occlusal plane. Such disruptive side effects can now be reduced thanks to a newly developed auxiliary module – the Class II Jig.
The Class II Jig consists of a thicker dimensioned round archwire, one end of which is welded to a Mini Sprint bracket for the maxillary canine and the other end is inserted into the tube of a molar attachment. This achieves optimal anchorage in the maxillary posterior region. Successful use of the Class II Jig requires completed alignment and levelling of the dental arch.
Virtually every Class II malocclusion therapy requires derotation of the first molars. Depending on the extent of the rotation, a compression spring can be used to the mesial of the molar tube in addition to the Class II Jig. If there is only a slight occlusal anomaly present, derotation of the first molar can simply be achieved by bending the wire accordingly.
Because of the stable connection of the canine and first molar, the forces of the intermaxillary elastics can be transmitted directly and without deviation to the maxillary first molar. Nevertheless there may be reactive side effects in the mandible such as extrusion of the mandibular molars and consequently to deviation of the occlusal plane. To counteract these effects from the outset, it is recommended to use a lingual arch to provide additional anchorage in the mandible. Alternatively skeletally inserted mini-screws can also be used.