Many patients who come to the orthodontist have a protrusion of the upper teeth over the lower teeth. This is called a Class II Malocclusion, and usually results from one of three situations: 1) an overgrowth of the upper jaw, 2) a deficiency or lack of forward growth in the lower jaw, or 3) a combination of the two. Since the problem is related to growth or size of skeletal structures (the jaw bones), it is necessary to reposition these bones in order to achieve a satisfactory dental and cosmetic result and a face that is in balance with the surrounding muscles.
In an adult or non-growing patient, slight Class II corrections can be accomplished with normal orthodontic appliances. More severe Class II problems require surgery to reposition the jaw bone or bones that are out of balance.
In the growing child, orthodontic appliances can be used to alter the growth of the jaws so that they come into balance and a surgical procedure is avoided. In the case of a Class II due to an excessive forward growth of the upper jaw or underdevelopment of the lower jaw, a fixed device called a herbst or a removal applicance called a headgear can be utilized in conjunction with braces.
The advantage of the herbst appliance is that it requires minimal cooperation from the patient in order to accomplish the desired goal.
