Conventional orthodontics utilizes fixed braces such as brackets and bands. Often rubber bands and other force systems (neckgears, springs, etc.) are then attached to the braces to effectively move or direct the teeth and/or jaws to the desired position(s). There are those patients who have problems that primarily involve the jaws where conventional braces may not be adequate to correct the bite. In these instances, orthodontists utilize other force systems to promote an increase in jaw growth that would not ordinarily occur with fixed appliances alone. These removable appliances are called "functional appliances."
Functional appliances are designed to modify growth and are used primarily for those patients with a deficient lower jaw. Success can only be achieved through consistent, full-time wear of the appliance. The Herbst appliance, unlike many other functional appliances (Bionator, Twin Block, Frankels, etc.), is fixed, or cemented, to the teeth. This means that the Herbst appliance is working 24 hours a day to maximize growth modification. The Herbst appliance allows for adequate range of motion of the jaws and minimally impacts speech. Most patients will find the Herbst appliance surprisingly easy to wear.
Growth modification is most effective during the greatest period of growth for children (9-14 years of age). After the initial fitting appointments, the appliance is adjusted every 2-3 months and is usually worn for a total of 9-12 months. Limited upper and lower braces may be used during Herbst treatment. The main goal, however, is the correction of the jaw discrepancy. Following the removal of the Herbst appliance, comprehensive orthodontics will be initiated to finalize the bite for the greatest stability and esthetics.