Comparison of three diff erent orthodontic wires for bonded lingual retainer fabrication

Objective: We evaluated the detachment force, amount of deformation, fracture mode, and pull-out force of 3 different wires used for bonded lingual retainer fabrication. Methods: We tested 0.0215-inch five-stranded wire (PentaOne, Masel; group I), 0.016 × 0.022-inch dead-soft eight-braided wire (Bond-ABraid, Reliance; group II), and 0.0195-inch dead-soft coaxial wire (Respond, Ormco; group III). To test detachment force, deformation, and fracture mode, we embedded 94 lower incisor teeth in acrylic blocks in pairs. Retainer wires were bonded to the teeth and vertically directed force was applied to the wire. To test pull-out force, wires were embedded in composite that was placed in a hole at the center of an acrylic block. Tensile force was applied along the long axis of the wire. Results: Detachment force and mode of fracture were not diff erent between groups. Deformation was signifi cantly higher in groups II and III than in group I (p < 0.001). Mean pull-out force was signifi cantly higher for group I compared to groups II and III (p < 0.001). Conclusions: Detachment force and fracture mode were similar for all wires, but greater deformations were seen in dead-soft wires. Wire pull-out force was signifi cantly higher for fi ve-stranded coaxial wire than for the other wires tested. Five-stranded coaxial wires are suggested for use in bonded lingual retainers. [Korean J Orthod 2012;42(1):39-46]