摘要 |
When an orthodontic appliance is attached to the lingual side (back side) of teeth which is invisible from the outside, a large difference in level of the surface between adjacent teeth requires utilization of a wire bent in a complicated fashion. It has been found, however, that the difference in level between adjacent teeth is very small in a horizontal plane at a boundary between a crown and a root, thereby making it possible to draw a smooth envelope therealong. Based on this finding, with a view to placing a wire along such an envelope, a "lingual straight archwire" having a planar configuration comprising a simple curve and straight lines smoothly connected to ends of the curve and residing in a single horizontal plane and a bracket having a configuration suitable for the placement of the archwire are provided.
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