CLASS II CORRECTION: FUNCTIONAL APPLIANCES OR HEADGEAR, EXTRACTIONS OR MINI-IMPLANTS
Class II malocclusion is defined by a molar tooth relationship where the lower mandibular molar is back relative to the upper maxillary molar.
There are 15 types of Class II.
The maxillary teeth can be protrusive, the maxilla can be protrusive, the mandible can be retrusive, the mandibular teeth can be retrusive, the maxilla can be retrusive and the mandible can be retrusive, etc… , and vertical dimension can affect these relationships as well.
Treatment can vary depending on the tooth positions, jaw bone positions and availability of growth in the appropriate direction.
Not all Class 2’s are alike by Dr. Standerwick (AJODO Vol. 136, Issue 2, Page 143)
Is useful when lower incisors are inclined forward or if the bite plane displays a significant curve. It is good for reducing a gummy smile or and probably the best option for increasing the vertical height. Growth is necessary. Compliance can be an issue. Required wear is approximately 12-16 hrs.
Per day to obtain approximately 1mm per month of movement.
Various named functional appliances do basically the same thing. The push the lower mandible jaw forward in an attempt to stimulate growth; there is also a “headgear effect”. The more growth available, the more lower mandible jaw movement occurs and with less growth the lower mandibular teeth will move forward relative to the lower jaw. This can force the mandibular teeth forward, stressing the gum tissues enough to risk the need for gum grafting (take a patch of tissue from the palate to be placed over the lower mandibular anterior teeth roots.
Elastic bands are useful for short periods with certain facial types. They can make long faces longer and increase the gumminess of smiles. Compliance can be an issue.
With less available growth, one must consider extraction of permanent teeth, TADs or surgery depending on esthetic demands and boney confines.
Require minor surgery for placement and they can become loose and require replacement. Besides that, all patients have stated they are fine and do not bother them. Occasionally, 3rd molars (wisdom teeth) may need to be extracted. Tooth movements can be slow and increase treatment time. They do not require the cooperation needed for headgear.