[The lateral and transverse forces with indirect headgear and its modifications]

The use of the various variants of indirect headgear engenders transversal and lateral forces as an inevitable side effect. Direct clinical assessment of these forces, however, is not possible. To deal with this problem the study presented here employed 3D force sensors to measure in vitro the sagittal and transversal forces generated by diverse headgear modification. The results show that the transversal and lateral forces reach magnitudes which have direct clinical relevance. A common symmetrical indirect headgear, for instance, generates an expansive force that amounts to 20% of the distal. Transversal forces generated by expansion and compression headgear rapidly exceed therapeutically desirable magnitudes. All asymmetric headgear included in the study produced lateral forces which may lead to unwanted scissor or cross bites. The study presents a method whereby these inevitable lateral forces engendered by asymmetric headgear can potentially be minimized.