Factors related to the control of maxillary anterior teeth torque in invisible appliances

Invisible appliance technology is a novel orthodontic technology that uses computer aided design and polymer materials to achieve a more aesthetic and comfortable treatment. Compared with traditional lip-bracket orthodontic treatments, the greatest advantages of an invisible appliance are aesthetics. In the orthodontic process, the control of the anterior teeth may not be accurate, which often directly affects the patient′s postoperative side appearance; however, in clinical practice, there is still a large deficiency in the control of the anterior tooth torque by an invisible appliance compared to traditional lip-bracket orthodontic treatments. The factors related to the expression efficiency of anterior tooth torque include the combination of morphology and position of different types of brackets and wires, the tooth movement mode and clincheck design. This article reviews the factors that influence lingual orthodontics and clear aligner therapy in the treatment of anterior tooth torque.