Patients with a Class II Division 2 skeletal relationship usually have a combination of a retroclined premaxilla, lingually tipped centrals with overlapping labially placed laterals and a posteriorly placed mandible that is locked into this position by a deep bite. The first step in correcting this problem is to treat the maxilla by developing the arch in an anterior-posterior direction.

The primary objective of the Sagittal appliance shown here is to develop the premaxilla. This is accomplished by the activation of the expansion screws and by utilizing extra anchorage created by intercuspating the opposing arch with the posterior bite plane. Once this is accomplished the laterals can be guided lingually into place with T-springs.

Note - A combination ot anterior and posterior occlusal bite planes are commonly used in Sagittal appliances. A wax bite allowing about 1 to 1-1/2 mm of vertical opening, measured between the most posterior teeth in the arch, is needed to properly fabricate the appliance. This bite should be taken in the patient's natural centric position.