Nabbat Sarah A, Yassir Yassir A
Department of Orthodontic, College of Dentistry, University of Baghdad, Iraq.
Eur J Orthod. 2020 Dec 2;42(6):626-634. doi: 10.1093/ejo/cjz102.
To compare the heat-activated nickel titanium (HANT) with superelastic nickel-titanium (SENT) archwires in terms of their effectiveness of aligning teeth, possibility of inducing root resorption, and perception of pain.
Orthodontic patients aged 12 years or over with mandibular anterior crowding of 3-6 mm, who required treatment without extractions were randomly allocated (a simple non-stratified randomization) to the HANT and SENT archwires groups with a 1:1 allocation ratio. The archwire sequence in both groups was 0.014-inch and 0.016-inch, respectively. Each archwire was placed for 4 weeks. The outcome measures included the amount of crowding assessed blindly using Little's irregularity index (LII), apical root resorption, and pain perception. The effectiveness of alignment was tested using 2 × 2 mixed factorial analysis of variance (ANOVA) model, while root resorption and pain perception were tested by the Mann-Whitney U-test and Wilcoxon signed-rank test (P < 0.05).
Thirty-four patients were randomized and recruited from four centres, of those 31 were analysed (15 participants for the HANT and 16 for the SENT groups) with an overall mean age of 19.13 ± 5.73 years. The total reduction in the LII was 2.69 mm and 2.74 mm for the HANT and SENT groups, respectively. This did not reach the level of statistical (P = 0.809) or clinical significance. Similarly, root resorption and pain perception showed non-significant difference between groups. However, there was a slight increase in root resorption with the SENT group.
A long-term evaluation of root resorption is required.
Both HANT and SENT archwires were equally effective in the aligning stage of orthodontic treatment. Root resorption with SENT wires should be monitored throughout treatment.
The trial was registered with ClinicalTrials.gov on 18 September 2019, registration number: NCT04090931.
比较热激活镍钛（HANT）弓丝和超弹性镍钛（SENT）弓丝在排齐牙齿的有效性、诱导牙根吸收的可能性以及疼痛感受方面的差异。
年龄在12岁及以上、下颌前牙拥挤3 - 6毫米且无需拔牙治疗的正畸患者，通过简单非分层随机化以1:1的分配比例随机分配至HANT弓丝组和SENT弓丝组。两组的弓丝序列分别为0.014英寸和0.016英寸。每根弓丝放置4周。观察指标包括使用Little不规则指数（LII）盲法评估的拥挤量、根尖牙根吸收情况以及疼痛感受。排齐效果采用2×2混合方差分析（ANOVA）模型进行检验，而牙根吸收和疼痛感受则通过Mann-Whitney U检验和Wilcoxon符号秩检验进行检验（P < 0.05）。
从四个中心随机招募了34例患者，其中31例进行了分析（HANT组15例，SENT组16例），总体平均年龄为19.13±5.73岁。HANT组和SENT组LII的总减少量分别为2.69毫米和2.74毫米。这未达到统计学意义（P = 0.809）或临床意义水平。同样，两组之间的牙根吸收和疼痛感受无显著差异。然而，SENT组的牙根吸收略有增加。
需要对牙根吸收进行长期评估。
在正畸治疗的排齐阶段，HANT弓丝和SENT弓丝同样有效。在整个治疗过程中应监测SENT弓丝导致的牙根吸收情况。
该试验于2019年9月18日在ClinicalTrials.gov注册，注册号：NCT04090931。
