Treatment of a Class II malocclusion with computer-aided design and manufacture of a fixed Twin-block appliance combined with customized labial brackets

Abstract

• Fixed Twin-block appliance combined with customized labial bracket can treat Class II malocclusion. • CAD/CAM technology contributed to the manufacture of the appliances. • Fixed Twin-block brought satisfactory treatment outcomes. • Treatment outcomes were better in adolescents than in adults. Class II malocclusion is common in clinical practice, and Twin-block appliances have been widely used for orthopedic treatment. This article introduces the design and clinical application of a fixed Twin-block appliance combined with a customized labial bracket. Computer-aided design and manufacturing (CAD-CAM) technologies were used to design and manufacture the appliances. The components of the Twin-block appliance were manufactured by casting them in a 3-dimensionally printed wax analog and were connected through laser welding. Customized labial fixed appliances were manufactured with CAD-CAM technology and bonded using indirect bonding. The acrylic resins used to fill the occlusal surface were gradually ground during fixed orthodontic treatment. These appliances were used to treat a 13-year-old girl and a 33-year-old woman presenting with Class II malocclusion with mandibular retrusion and large overjet. The fit of the CAD-CAM-generated appliances was precise, and they helped shorten the treatment period. Superior treatment outcomes improve the prospects of functional orthodontic treatment.