Department of Experimental and Clinical Medicine, The University of Florence, Italy.
Department of Clinical Sciences and Translational Medicine, University of Rome Tor Vergata, Italy.
Eur J Orthod. 2021 Jun 8;43(3):293-300. doi: 10.1093/ejo/cjaa063.
The objective of this study was to compare an expansion screw of the maxilla that generates moderate and continuous forces versus a conventional screw for rapid maxillary expansion (RME) on patient-reported outcome measure during the first 12 weeks of treatment.
This is a superiority, multicenter, two-arm parallel balanced randomization trial.
Patients in the mixed dentition were included with a transverse discrepancy between the two arches of at least 3 mm. An expansion screw using moderate continuous forces (Leaf group, treated with an expansion screw with Ni-Ti springs) was compared to a conventional RME screw that generates intermittent heavy forces (RME group). The primary response variable was the visual analogue scale (VAS) on pain calculated in the first 12 weeks of therapy. The VAS on difficulty on speaking and oral hygiene, patient satisfaction, and complications were also evaluated. A computer-generated block randomization was used with allocation concealed in sequentially numbered opaque-sealed envelopes. Blinding was not applicable. Linear models were used for statistical analysis.
Twenty-eight patients in the Leaf group and 28 patients in the RME group were randomized and included in the study. There were no dropouts. The mean of the VAS for pain was 0.3 ± 0.4 in the Leaf group and 0.6 ± 0.5 in the RME group. The difference was -0.3 (95 per cent CI from -0.5 to -0.0; P = 0.017) in favour of the Leaf group. The difference in pain was marked in the first week (Leaf group 2.2 ± 2.3; RME group 3.7 ± 2.6; difference -1.5; 95 per cent CI from -2.7 to -0.3; P = 0.019).
Patients in the Leaf group experienced a lower degree of pain, especially during the first week following the application of the expander. For the other variables, no significant differences were reported between the two treatments.
The study was registered in the ISRCTN register on 8 November 2016 with the number ISRCTN18263886.
本研究旨在比较上颌扩张器产生适度持续力与传统快速上颌扩张（RME）螺钉在治疗的前 12 周内对患者报告的治疗结果测量中的差异。
这是一项优越性、多中心、双臂平行平衡随机试验。
本研究纳入混合牙列患者，其上下颌骨之间的横向差异至少为 3mm。使用中度持续力的扩张器（Leaf 组，用镍钛螺旋弹簧治疗）与产生间歇性大力量的传统 RME 螺钉（RME 组）进行比较。主要反应变量为治疗的前 12 周内的疼痛视觉模拟量表（VAS）。还评估了说话和口腔卫生困难、患者满意度和并发症的 VAS。使用计算机生成的块随机化，分配隐藏在顺序编号的不透明密封信封中。未实施盲法。线性模型用于统计分析。
28 名患者被分配到 Leaf 组，28 名患者被分配到 RME 组，所有患者均随机分组且纳入研究。无脱落病例。Leaf 组的平均 VAS 疼痛评分为 0.3±0.4，RME 组为 0.6±0.5。两组之间的差异为 -0.3（95%置信区间为 -0.5 至 -0.0；P=0.017），有利于 Leaf 组。Leaf 组在第一周的疼痛差异显著（2.2±2.3；3.7±2.6；差异 -1.5；95%置信区间为 -2.7 至 -0.3；P=0.019）。
Leaf 组患者在应用扩张器后的第一周内经历了较低程度的疼痛，特别是在第一周。对于其他变量，两种治疗方法之间没有报道有显著差异。
该研究于 2016 年 11 月 8 日在 ISRCTN 登记处注册，编号为 ISRCTN85433264。
