The Trans-Palatal Arch (TPA), also known as Goshgarian arch, is a wire element attached to the first molars in the upper jaw. The TPA is made up of stainless steel wire with a diameter of 0.9mm and inserted into special locks on orthodontic bands. The TPA makes it possible to rotate, tilt and physically move the 1st molars outwards and, to a certain extent, also backwards and forwards. The Trans-Palatal Arch is one of the most effective appliances, that successfully carries out its duties without needing constant maintenance or an over-whelming hindrance on daily life.
Unfortunately, German orthodontists often prefer the obsolete active plate because working with TPA requires good knowledge and a certain degree of technical skill. The active plate is not nearly as efficient for the tasks mentioned as the TPA and impairs speech at a high degree.