Efficient Deep Bite Correction With Clear Aligners

Class II division 2 malocclusion is often associated with class II molar relationships and deep overbite. Conventional treatment involving maxillary molar distalization alone may result in suboptimal results. This study proposes a combined approach: simultaneous distalization and extrusion of both maxillary and mandibular molars, supplemented with intermaxillary elastics for sagittal correction. This method efficiently opens the bite while reducing the required molar distalization. A 39-year-old female presented with a chief complaint of deep overbite and poor masticatory function. Medical history was non-contributory. Intraoral examination revealed a permanent dentition with a Class II molar relationship, overbite III°, and lingually inclined incisors. Skeletal analysis indicated a Class I pattern, hypodivergent growth, and straight profile. Treatment involved clear aligners (36 stages, V-pattern design, full-time wear with weekly changes). Simultaneous distalization and extrusion of molars were performed, supplemented with short Class II elastics in the mid-late phase. Satisfactory occlusion was achieved in 9 months. For Class II division 2 cases, traditional clear aligner protocols often rely on maxillary molar distalization and incisor proclination to open the bite. However, inadequate vertical control may lead to inefficient tooth movement. Molar distalization with extrusion was used to enhances vertical dimension control, achieving faster overbite correction with less distalization. Concurrent molar distalization and extrusion, guided by intermaxillary elastics, efficiently corrects deep overbite while minimizing distal displacement. This strategy optimizes biomechanics in clear aligner therapy for complex Class II division 2 cases.