摘要 |
The invention provides an orthodontic arch wire of particular cross-section for use with an orthodontic bracket as disclosed in my earlier patent Ser. No. 3,772,787. This bracket has a mesial-distal extending slot to receive the arch wire, the labial face of which is closed by a sliding U-shaped spring retainer member, one end of which protrudes into the slot to engage the arch wire labial face. The wire cross-section has straight parallel occlusal and gingival sides with the occlusal longer than the gingival. The lingual side is also straight and at right angles to the occlusal and gingival sides. The labial side that is contacted by the retainer member is outwardly convex curved about a radius within the cross-section, the preferred ratio of occlusal side length to radius being from 1:0.4 to 1:0.76.
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