Christchurch Orthodontics Ltd. - Russell Lovatt & Christine Bailey

Functional Appliances

Functional ApplianceAny appliance that utilises the functional forces from the muscles of the jaw and face to correct the bite is termed a ‘functional appliance’. They have been used in orthodontics since the 1930’s and are mainly for those patients who have prominent upper front teeth and a small lower jaw.

Traditionally these have been removable plates or fixed piston devices which displace the lower jaw forward. Functional appliances initially feel quite bulky and will stretch the jaw muscles. Speech and swallowing may be difficult at first but after a few days the appliance will become more comfortable. Once the lower jaw is held in a forward postured position, the muscles of the jaw and face, apply pressure to the functional appliance. Over time these forces move the teeth.

Bionators and Twin Blocks are common examples of removable functional braces.  These are often used to reduce large overjets and reduce the prominence of the upper front teeth.  They can be used at an earlier stage of dental development than the conventional fixed braces and work best if worn consistently both day and night over a 6 – 12 month period.  Fixed appliances may still be needed following a functional brace to achieve individual tooth alignment.