Twin Block
This design is for Class II correction using inclined occlusal blocks to hold the mandible. The angle of inclination of the occluding surface is 70 degrees. In the upper jaw, one or two expansion screws expand and correct the anterior dentition. The function of the Twin Block appliance is achieved by using a construction bite at the height at least 6 mm vertically, and secures retention of the upper and the lower arch.
