Dr. William Clark, an Orthodontist, developed an uncomplicated technique that incorporates the use of upper and lower bite blocks to reposition the mandible forward for skeletal Class II correction. The Twin Block technique is easy to use and very patient friendly. The design utilizes two separate appliances that fit the maxilla and mandible. The unique design allows for more patient comfort and increased patient cooperation. The Twin Block design also allows for independent development of the upper and lower arches with the addition of transverse and/or sagittal screws.
Standard Twin Block
Twin Block To Close
Sagittal Twin Block
McNatt Twin Block
Dr. James McNamara designed Twin Block includes two upper expansion screws for maxillary arch development. To enhance retention of the lower portion of the appliance a labial bow with acrylic is added to the design. In addition, the lower flanges of acrylic are extended to the molars.
Twin Block Stage II
Once “three-point” contact has been achieved a fixed or removable incline bite plane is used to support Class II correction. The Stage II appliance is used until the bicuspids have erupted into occlusion and the posterior open bite has been closed.