Schmid Jonas Q, Katsaros Christos, Sculean Anton, Galletti Catherine, Bettenhäuser-Hartung Lara, Janssens Yann
Quintessence Int. 2025 Apr 22;56(4):306-317. doi: 10.3290/j.qi.b5984435.
Wire syndrome or X-effect/twist-effect describes undesired long-term tooth movements following fixed retainer placement. Since it includes root torque changes that might cause gingival recession, those situations often require periodontal, orthodontic, and conservative treatment. The aim of this study was to assess the effectiveness of fixed orthodontic treatment with completely customized lingual appliances (CCLAs) and continuous archwires for a clinically significant reduction in the dimensions of labial gingival recessions in the anterior mandible, caused by wire syndrome, in a group of consecutive patients treated with the same approach. Moreover, the reduction in root prominence of the affected teeth relative to the two neighboring teeth was evaluated.
This retrospective cohort study from three centers included 20 consecutively recruited patients with labial gingival recession at mandibular incisors and canines due to wire syndrome. A total of 25 teeth were assessed. CCLA treatment with a standardized archwire sequence (0.012″/0.014″ NiTi, 0.016″ × 0.022″ NiTi, 0.018″ × 0.018″ beta-titanium with optional extra-torque) was identical in all three centers. Primary endpoints of recession depth, recession width, and recession surface were assessed on digital models at debonding (T1) and compared to baseline (T0) both as absolute differences (T0 - T1), and as ratios ([T0 - T1]/T0) by one-sample t tests with P .05. As a secondary endpoint, the reduction of root prominence relative to the gingival surface of the alveolar yoke of the two neighboring teeth was measured in millimeters.
Treatment resulted in a significant reduction in all dimensions of gingival recession. The mean reduction in recession depth was 1.86 mm (44.9%) and in recession width 0.70 mm (35.6%). The mean recession surface was reduced from 10.77 mm2 to 3.93 mm2, indicating a mean recession surface reduction of 61.4%. All changes were statistically significant (P .001). The range of recession surface reduction was from 25.4% to 100%, and 18 out of the 25 recessions showed a reduction of more than 50%. The maximum reduction in root prominence amounted to more than 3 mm.
The use of CCLAs to torque roots of the anterior mandibular teeth, exposed by wire syndrome, towards the middle of the alveolar process reduces the area of subsequent labial gingival recession and reduces the root prominence of the affected teeth substantially. This is considered a critical step in optimizing the predictability of surgical recession coverage.
钢丝综合征或X效应/扭转效应描述了固定保持器放置后出现的不良长期牙齿移动。由于其包括可能导致牙龈退缩的牙根转矩变化，这些情况通常需要牙周、正畸和保守治疗。本研究的目的是评估采用完全定制的舌侧矫治器（CCLA）和连续弓丝进行固定正畸治疗，对一组采用相同方法治疗的连续患者中由钢丝综合征导致的下颌前部唇侧牙龈退缩尺寸进行临床上显著减小的有效性。此外，还评估了患牙相对于相邻两颗牙齿牙槽嵴牙龈表面的牙根突出度降低情况。
这项来自三个中心的回顾性队列研究纳入了20例因钢丝综合征导致下颌切牙和尖牙唇侧牙龈退缩的连续招募患者。共评估了25颗牙齿。在所有三个中心，采用标准化弓丝序列（0.012英寸/0.014英寸镍钛丝、0.016英寸×0.022英寸镍钛丝、0.018英寸×0.018英寸β钛丝并可选择额外加转矩）进行CCLA治疗。在拆除矫治器时（T1），在数字模型上评估退缩深度、退缩宽度和退缩面积等主要终点指标，并与基线（T0）进行比较，分别作为绝对差值（T0 - T1）以及通过单样本t检验得出的比值（[T0 - T1]/T0），P < 0.05。作为次要终点，测量患牙相对于相邻两颗牙齿牙槽嵴牙龈表面牙根突出度的降低量，单位为毫米。
治疗导致牙龈退缩的所有维度均显著减小。退缩深度的平均减小量为1.86毫米（44.9%），退缩宽度的平均减小量为0.70毫米（35.6%）。退缩面积的平均值从10.77平方毫米减小至3.93平方毫米，表明退缩面积平均减小了61.4%。所有变化均具有统计学意义（P < 0.001）。退缩面积减小的范围为25.4%至100%，25处退缩中有18处显示减小超过50%。牙根突出度的最大减小量超过3毫米。
使用CCLA将因钢丝综合征暴露的下颌前部牙齿的牙根向牙槽突中部扭转，可减少后续唇侧牙龈退缩的面积，并显著降低患牙的牙根突出度。这被认为是优化手术退缩覆盖可预测性的关键步骤。
