Clinical implications of recall visit ligature-tie activation on alignment efficiency in premolar extraction cases: a randomized controlled trial.

Objectives: To determine whether replacing stainless steel ligature ties during recall visits accelerates anterior tooth alignment (decrowding) in extraction cases. Materials and Methods: Twenty-four patients with a Little's Irregularity Index (LII) > 4, indicated for bicuspid extraction, were randomly assigned to two groups. All patients received preadjusted edgewise appliances and 0.016 Cu-NiTi initial archwires. Group 1 had ligature ties left in place until alignment completion; Group 2 had ties replaced every 4 weeks. Decrowding was quantified, until the LII score of 0 was achieved, measured at each 4-week interval using digital calipers on study models. Outcome assessors were blinded, and intraobserver and interobserver reliability was established. Results: No significant difference was noted in overall decrowding rate between groups (P = 0.765; Group 1: 68.7 ± 29.0 days; Group 2: 65.3 ± 24.9 days). In Group 2, the maxillary arch showed a faster decrowding rate than the mandibular arch (P = 0.012; 42.0 ± 16.2 vs 77.0 ± 19.8 days). No significant arch difference was found in Group 1. Conclusions: Changing stainless steel ligatures at each recall visit offers no substantial benefit in the overall rate of anterior alignment. Scheduling recall visits every 8 weeks may be recommended for efficient time management during the alignment phase.