I. Field of the Invention
The present invention relates generally to orthodontic appliances and, more particularly, to an orthodontic appliance for imposing an anterior traction of force on the patient's jaw.
II. Description of the Prior Art
In the practice of orthodontics, it is frequently necessary to move the patient's jaw anteriorly with respect to the patient's head in order to obtain a correct bite. This is especially true with the lower jaw of the patient.
There are a number of previously known appliances with are designed to move the patient's jaw forwardly by imposing anterior force on the patient's jaw. All of these previously known devices generally comprise a head gear or head assembly of one sort which is mounted to the patient's head so that a portion of the head gear is positioned in front of the patient's mouth. Thereafter, elastic members, typically rubber bands, extend between the appliance and the patient's jaw under tension in order to exert the anterior force on the patient's jaw.
As is well known in physics, for each force or reaction there must be an equal and opposite force or reaction. Consequently, in order to impose an anterior force on the patient's jaw, there must be an equal and opposite posterior force also imposed upon the patient.
Many of these previously known devices have thus used pads which engage either the cheekbone area or the chin of the patient. Consequently, when rubber bands are tensioned between the previously known orthodontic device and the patient's jaw, a posterior force is imposed by the appliance against either the patient's cheekbone area, the patient's chin, or both. The rearward or posterior force imposed upon the cheekbone or chin is opposite to and offsets the anterior force imposed on the patient's jaw.
However, both the chin as well as the cheekbones are interconnected with the patient's upper and lower jaws. Consequently, by imposing a posterior force on the cheekbones and/or the patient's chin, these previously known orthodontic appliances disadvantageously counteract the desired anterior force on the patient's jaw. Furthermore, in some cases, the posterior force imposed on the patient's chin and/or cheekbones result in some depression of the cheekbones and/or chin which detracts from the overall facial appearance of the patient.