Objective: Lingual arch (LA) has been used for improvement of the anterior crossbite, traction of the impacted teeth, space maintenance. However, there is a limitation on control of tooth movement using LA combined with the traditional fingerspring. We designed new LA to enable three-dimensional control of the tooth movement with lower counteraction on the adjacent teeth compared with multibracket appliance.
Materials and Methods: A headgear tube in a double buccal tube (0.018×0.025 inch slot) for the first molar was inserted to main arch of the traditional LA, and was fixed with silver solder. Pre-bended improved super-elastic Ti-Ni alloy rectangular wire (ISW) (0.018×0.025 inch) was inserted to its wire slot, and was used as the fingerspring of LA. The wire was set in the bracket slot installed to the teeth, or contracted with ligature wire.
Results and Discussion: This technique was applied to some cases as follows: impacted and malpositioned maxillary canine that was closed to root of the adjacent teeth; the transposition of the maxillary canine and premolar; anterior crossbite of the maxillary central incisor with rotation and disto-lingual tipping in unilateral cleft lip palate. Three-dimensional control of tooth movement including root control was achieved effectively using the LA combined with ISW. Moreover, the counteraction on the adjacent teeth was negligible.
Conclusion: This technique was useful for tooth movement required complicated three-dimensional control with low counteraction on the adjacent teeth.