| 摘要 |
An orthodontic spring is comprised of a wave spring made of shape memory alloy that consists of a wire tightly looped, once or many times back on itself, side-to-side in figure "8"fashion. After winding, the spring is heat treated into this position. In its relaxed state, the bends of the spring form peaks and valleys which lie in parallel planes at an angle to the line of force between attachment loops at opposite end points of the spring. Portions of the wire between successive peaks and valleys overlap other portions between other peaks and valleys when the wire is relaxed. When extended, the elements of the spring lie in a longitudinal plane along its line of force. The spring is particularly suited to attachment between closely spaced points, such as brackets affixed to adjacent teeth.
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