Class II Division 1 And Posterior Scissor Bite: Angelalign Therapy

This case highlights the efficacy of clear aligner therapy in addressing complex Class II division 1 malocclusion with unilateral posterior scissors bite, demonstrating a non-invasive approach for skeletal-dental and aesthetic improvement. A 9-year-old male presented with a convex facial profile, retrognathic mandible (SNB: 73.9°), excessive overjet (6.0 mm), and left posterior scissor bite. Cephalometric analysis confirmed a skeletal Class II pattern (ANB: 6.2°, Wits: +2.0 mm). Treatment involved sequential clear aligners (Angelalign, SmartTrack material; Angelalign Technology Inc.) over 12 months, incorporating precision cuts, optimized attachments, to correct crowding (Little’s index: 6 mm→0.5 mm) and resolve scissor bite. The aligner protocol achieved simultaneous mandibular advancement (SNB: 73.9°→76.4°, ANB: 6.2°→4.1°) and transverse correction, evidenced by posterior occlusal coordination and improved archform symmetry. Soft-tissue analysis revealed reduced facial convexity (Holdaway H-angle: 19°→14°) and enhanced lip competence. Compared to conventional fixed appliances, the aligner system provided superior vertical control (MP-SN: 46.4°→46.3°) while avoiding functional appliance dependency. Strategic staging of movements prioritized scissor bite resolution before sagittal correction, leveraging differential anchorage design. This case demonstrates that modern clear aligner systems can effectively manage combined sagittal-transverse discrepancies in mixed dentition, offering a patient-friendly alternative to fixed/functional appliances. Stable occlusion and balanced facial aesthetics at 12-month follow-up support their use for growing patients requiring multidisciplinary correction.