The bi-helix opening spring for lingual orthodontics.

U nlike treatment with conventional labial brack­ ets, lingual orthodontics relies on constriction mechanics, since the brackets are placed behind the center of resistance of the teeth. This makes space opening for the alignment of blocked­out anterior teeth one of the major challenges of lingual treatment. Insertion and compression of an open­ coil spring are difficult and technique­sensitive due to the narrow interbracket distances, even if a labi­ ally blocked­out tooth is not tied in to the archwire. A compressed archwire can produce unwanted side effects and will also have to bypass the blocked­out tooth, thereby increasing treatment time. An alternative to these methods, the bi­helix opening spring, is an inexpensive, custom­made auxiliary that is easily " clipped " into place after bonding and engagement of the blocked­out tooth, without removal of the archwire. Because align­ ment and space opening are performed simultane­ ously, treatment time is reduced. The spring can be attached to single or multiple teeth in either arch, and it has shown virtually no side effects. 1. Bend a small helix of approximately 1mm diameter in a straight .016" stainless steel wire with a small bird­beak or Jarabak plier. 2. After measuring the space needed between the first and second helices, mark the position of the second helix in the appropriate location on the wire (Fig. 1) and bend a second helix similar to the first. 3. Mark the legs of the spring with the locations of bends that will place the spring at the appropri­ ate height, usually the gingival margin (Fig. 2). and in the private practice of orthodon-tics in Jbeil and Gemmayze, Lebanon.