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, 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 corrects malocclusion in which the upper teeth are too far forward relative to the lower teeth because of deficient lower jaw growth. In the past, orthodontists used headgear for the same purpose. However, headgear was challenging to wear and depended on patient compliance.
This appliance is cemented onto the teeth, so it is not removable and requires no compliance. It allows for an adequate range of motion of the jaws and minimally impacts speech. It is typically worn for about 9–12 months and works 24 hours a day to maximize growth modification. Most patients will find the Herbst appliance surprisingly easy to wear.
Growth modification is most effective during the most significant period of growth for children (9-14 years of age). When it is initially placed, the Herbst Appliance moves the lower jaw forward to correct the bite. This new position of the lower jaw helps to enhance lower jaw growth and move the teeth into a more ideal bite. In a growing child, it is very predictable and provides excellent results.
There are variations in the construction of the Herbst Appliance. It may be attached to the teeth with orthodontic bands or stainless-steel crowns. The appliance often has an expansion screw in the middle of the palate to help widen the jaw. There may also be tubes on the outside of the upper molar bands or crowns that are used if braces and orthodontic wires are placed on the upper teeth.
Expect it to take 5-7 days to completely adjust to the Herbst Appliance. Initially, the patients will notice a change in their bites and chewing will be different. There are usually no poking or sore spots, and patients accommodate pretty quickly. The appliance is monitored closely until the proper amount of expansion has been obtained, and it is usually worn for 9-12 months to ensure growth.
The Herbst Appliance is very durable and requires no maintenance except for normal cleaning. Since the appliance lies in contact with the teeth, extreme care must be taken regarding oral hygiene. The patient should brush and floss well, use a daily fluoride mouth rinse before bedtime, and avoid all sticky and sweet foods that might cause decay. Particular attention should be paid to cleaning the area of the appliance adjacent to the gum tissue.
Depending upon the severity of the jaw discrepancy, it may be necessary to activate the Herbst appliance during treatment. This will usually be done every few months until the proper jaw position is achieved when the appliance is being worn. The activation of the appliance involves placing small pieces of tubing on the lower arms of the appliance. If the tubing comes loose from the appliance, this should be reported immediately to the office.
If a bonded part of the appliance becomes loose, this should be reported to the office immediately. In addition, if any irritation of the soft tissues of the cheeks or lips occurs or if there is an unpleasant smell or taste occurring in the mouth, this should also be reported. There is a replacement fee for the replacement of the Herbst appliance, so please encourage your child to be very careful when wearing and handling the appliance. Should replacement be necessary, new impressions would need to be made.
Following the removal of the Herbst appliance, treatment continues with traditional braces or Invisalign to achieve dental alignment and finalize the bite for the greatest stability and esthetics. If you have any questions regarding treatment with the Herbst appliance, please do not hesitate to contact our office at your earliest convenience.
