Treatment of Skeletal Class III Malocclusion with Spaced Arch and Anterior Crossbite Using Low-Hysteresis Improved Super-Elastic Ti-Ni Alloy Wire (ISW)

This article presents the orthodontic treatment of a non-surgical, non-growing skeletal Class III malocclusion using an Improved Super-elastic Ti-Ni Alloy Wire (ISW), developed by the Institute of Science Tokyo (formerly Tokyo Medical and Dental University). Teeth 28 and 48 were extracted, and ISW with long Class III intermaxillary elastics (L3–U6) was applied to eliminate anterior occlusal interference, retract the mandible, and induce a clockwise rotation of the mandibular plane. In addition to mandibular space closure, the deviated dental midline and chin asymmetry were corrected using elastic chains and intermaxillary elastics. Proper arch coordination, space management, and midline alignment were achieved, resulting in an improved facial profile after 24 months of treatment.