Discipline of Orthodontics and Paediatric Dentistry, School of Dentistry, Faculty of Medicine and Health, The University of Sydney; Department of Orthodontics, Sydney Dental Hospital, Sydney Local Health District, Surry Hills, Australia.
Clinic of Orthodontics and Pediatric Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland.
Eur J Orthod. 2021 Jun 8;43(3):254-264. doi: 10.1093/ejo/cjaa031.
To assess upper airway volume changes after rapid maxillary expansion (RME) with three different expanders.
Three-arm parallel randomized clinical trial.
Sixty-six patients, 10-16 years old, in permanent dentition, with maxillary transverse deficiency were recruited and assigned with block randomization (1:1:1 ratio) and allocation concealment to three groups of 22 patients each (Hyrax, Hybrid-Hyrax, and Keles keyless expander). The primary outcome (overall upper airway volume change) and secondary outcomes (volume changes in the nasal cavity, nasopharynx, oropharynx, and hypopharynx) were blindly assessed on the initial (T0) and final (T1, 6 months at appliance removal) cone beam computed tomography. Differences across groups were assessed with crude or adjusted for confounders (gender, age, growth stage, skeletal pattern, baseline airway volume, and amount of expansion) linear regression models.
Fifty-one patients were analysed (19, 19, and 13 in the Hyrax, Hybrid-Hyrax, and Keles groups). Maxillary expansion resulted in considerable increases in total airway volume in the Hybrid-Hyrax group (+5902.1 mm3) and less in the Hyrax group (+2537.9 mm3) or the Keles group (+3001.4 mm3). However, treatment-induced changes for the primary and all secondary outcomes were of small magnitude and no significant difference was seen among the three expanderes in the total airway volume in either crude or adjusted analyses (P > 0.05 in all instances). Finally, among pre-peak patients (CVM 1-3), the Hybrid-Hyrax expander was associated with significantly greater increases in total airway volume compared to the Hyrax expander (P = 0.02).
RME resulted in relatively small increases in total upper airway volume and its separate compartments, with mostly no statistically significant differences across the Hyrax, Hybrid-Hyrax, and Keles groups.
Significantly greater attrition was found in the Keles group due to appliance failure. The current trial might possibly be under-powered to detect differences between groups, if such exist.
Keles expanders blocked during activations and required substitution for completion of treatment.
The protocol was not published before trial commencement.
Australian and New Zealand Clinical Trial Registry (ACTRN12617001136392).
评估三种不同扩弓器对上颌骨快速扩弓（RME）后的气道容积变化。
三臂平行随机临床试验。
66 名年龄在 10-16 岁、恒牙期、上颌骨横向发育不足的患者，采用区组随机化（1:1:1 比例）和分配隐藏法分为三组，每组 22 名患者（Hyrax、Hybrid-Hyrax 和 Keles 无钥匙扩弓器）。主要结局（总气道容积变化）和次要结局（鼻腔、鼻咽、口咽和下咽的容积变化）在初始（T0）和最终（T1，矫治器去除后 6 个月）锥形束 CT 上进行盲法评估。使用未经调整和调整混杂因素（性别、年龄、生长阶段、骨骼模式、基线气道容积和扩弓量）的线性回归模型评估组间差异。
51 名患者纳入分析（Hyrax、Hybrid-Hyrax 和 Keles 组分别为 19、19 和 13 名）。上颌骨扩弓导致 Hybrid-Hyrax 组总气道容积显著增加（+5902.1mm³），Hyrax 组增加较少（+2537.9mm³）或 Keles 组增加较少（+3001.4mm³）。然而，主要和所有次要结局的治疗诱导变化幅度较小，在未经调整和调整分析中，三种扩弓器在总气道容积方面均无显著差异（所有情况下 P>0.05）。最后，在预高峰患者（CVM 1-3）中，与 Hyrax 扩弓器相比，Hybrid-Hyrax 扩弓器与总气道容积显著增加相关（P=0.02）。
RME 导致总上气道容积及其各部分容积的相对较小增加，Hyrax、Hybrid-Hyrax 和 Keles 组之间大多无统计学显著差异。
由于矫治器故障，Keles 扩弓器组的失访率显著增加。如果存在差异，当前试验可能没有足够的能力来检测组间差异。
Keles 扩弓器在激活过程中被堵塞，需要更换以完成治疗。
试验开始前未发布方案。
澳大利亚和新西兰临床试验注册中心（ACTRN12617001136392）。
