The Twin Block appliance is a removable functional appliance used to treat patients with excessive protrusion of the upper front teeth. The name “Twin Block” is derived from the fact that the appliance is comprised of separate upper and lower plates with ramps (blocks) that work in tandem. The appliance is very effective when patients are entering their adolescent growth spurt and acts to posture the lower jaw forward to move the teeth into a more harmonious position.
A Twin Block is considered more comfortable than some other fixed orthodontic orthopedic appliances. As the appliance is also removable, it is easier to maintain excellent oral hygiene during treatment. Appliances are generally removed when eating and playing sport. Speech can often be affected in the short term (they may experience a slight lisp) but like any other orthodontic appliance, patients will adjust after several days.
The appliance is generally worn full time to achieve bite correction. Patients with a Twin Block appliance will see the orthodontist every 8-10 weeks to check progress and adjust the appliance as needed. Treatment time with Twin Blocks is usually 12-18 months, however this will depend on the age and growth pattern of the patient. Early treatment with a functional appliance will often be followed by comprehensive orthodontic treatment with appliances such as braces to achieve ideal alignment and complete bite correction.
Written By Yvette Ding (Orthodontic Therapist)