Lower lingual fixed appliance
A lingual arch is an orthodontic device which connects the two six year old molars in the upper or lower dental arch. The lower lingual arch (LLA) has a wire adapted to the lingual side of the lower teeth. In the upper arch the archwire is usually connecting the two molars passing through the palatal vault, and is commonly referred as "Transpalatal Arch" (TPA).

LLA and TPA are fabricated by placing bands on the molars. These are connected to the archwire. The wire can be soldered to the bands or inserted into lingual sheaths welded to the molar band (removable LLA and TPA).

Lower removable appliance
Some orthodontic problems, if caught early enough can be corrected by an orthodontic plate. This is a removable appliance that can move teeth using wires, springs and expansion screws that guide teeth toward their correct position. Generally, plates are worn all the time, unless advised otherwise by your orthodontist. They do take some getting used to over a few days, but beyond that orthodontic plates are usaully quite comfortable to wear.