Control of anterior torque with a fully customized lingual appliance

Abstract

To achieve optimum occlusion and facial esthetics, it is important to control the anterior torque and anchorage. Especially in a patient with anterior protrusion, correct positioning of the maxillary and mandibular anterior teeth, and effective anchorage control are essential, and retraction of the anterior teeth represents a fundamental critical stage in orthodontic treatment. [1][2][3] In lingual orthodontic treatment, one of the most challenging issues has been torque control of the anterior teeth during space closure, [4] and there is a tendency for excessive lingual tipping of the maxillary anterior teeth. [5] Moreover, even minor incorrect torque has a considerable impact on the vertical tooth position. Previous studies showed that the impact on the anterior teeth is approximately 1.2 mm of vertical impact per 10° of incorrect torque.In recent years, computer-aided design and computer-aided manufacturing (CAD/CAM) software, rapid prototyping and robotic wire bending apparatus, have facilitated the development of a fully customized lingual appliance systems, Incognito™ lingual appliances. In a fully customized lingual bracket appliance, the desired anterior retraction with proper torque control is attained by vertical slots of low profile bracket and ribbon-wise wires. [6,7] This article describes a female patient with a skeletal Class II retruded mandible who was successfully treated with a fully customized lingual bracket system for controlling anterior torque and anchorage and for maintaining the vertical dimensions. cAse RePoRtThis patient was a 26.1-year-old female. She came to us with a chief complaint of anterior dental crowding and anterior protrusion. She was diagnosed as a skeletal and dental Class II. Because of inquiry for the invisible appliance, the customized lingual appliance, Incognito™ system, was employed.