[Indication and effectiveness of the J-hook headgear].

In this article the three most important types of J-hook headgears, the horizontalpull, the high-pull and the verticalpull are demonstrated. Indications of these headgearsamples are the (asymmetrical) retraction of teeth and groups of teeth, intrusion of anterior teeth including a very effective support of torque control, inhibition of horizontal and vertical growth of maxilla and mandible, compensation of side effects of Class I and Class III rubberbands, midline-corrections and retention following surgical correction of open bites. The headgear force can either be distributed directly on the teeth to be moved, on hooks which are soldered on the archwire, on chin caps or mandibular troughs resp. on functional appliances. The advantages of the J-hook headgear are an excellent control of anchorage, the variability (primarily of the vector of forces), but also a consistency after having established the assigned force vector, a consistency which also includes the amount of choosen force. Further advantageous is the simultaneous retraction of teeth in both arches as is the easy and safe handling of this headgear by patients and by the orthodontic team. In contrast to these outstanding advantages there are only very few disadvantages. These have mainly to be seen in a tendency of dental arch expansion and the rare occurrence of certain pressure induced problems in the soft tissues of the skull. In the first case a constriction of the archwire and even more a transpalatal arch will help to prevent this from happening. In the second case the best counter measure is the use of accessory soft pads.