This appliance is used in situations where the lower jaw (and teeth) have developmentally been "held back" (skeletally) in relation to the
upper teeth and jaw. It is used where the skeletal problem is too great for braces alone to resolve a short lower jaw and to resolve major "overbites") .The Herbst appliance,
while not always effective in making complete skeletal corrections, will often minimize the need for orthognathic surgery (jaw surgery). 
It tends to improve the chances that subsequent braces alone will yield acceptable treatment outcomes.
From time to time we will incrementally add parts to the appliance to posture
the lower jaw forward, hoping that growth will be re-directed to result in permanent, positive changes in the skeletal foundation.
In the beginning, it can be mildly challenging to learn to chew within the
limits of the appliance, but is soon mastered by nearly all patients.
To see how this appliance works first hand click the corresponding link below to see the video. It may be benificial to watch in 128k mode even if
you are on a slower dial-up modem for clarity, although it will take longer to download.
