关键词: 活动矫正器, 正畸牵引, 龈下断根, activity correction device, orthodontic traction, subgingival root pruning

Abstract: Objective To discuss the clinical application of the removable appliances in traction of subgingival root extrusion of anterior teeth . Methods 10 subgingival roots of anterior teeth with crown-root fracture of 6 cases were selected. After complete root canal therapy had been finished, the traction was implemented with maxillary removable appliances. The scaffolds of the removable appliances were bended with the 0.8mm stainless steel wires, which were against the mesial surfaces of the adjacent teeth and parallel to the long axess of the subgingival roots. Finally, sections were exposed at the position 5.0mm above or flush with the gingival margins. Results All the 10 roots were 3.0-5.0mm above the gingival margin. After crown restoration, 1 root was loose byⅠ°, and the other 9 roots were satisfactory 12 months later. Conclusion Active orthotic devices are simple and feasible for traction of subgingival root extrusion of anterior teeth.