Myrlund Rita, Dubland Mari, Keski-Nisula Katri, Kerosuo Heidi
*Institute of Clinical Dentistry, Faculty of Health Sciences, University of Tromsø, Norway,
*Institute of Clinical Dentistry, Faculty of Health Sciences, University of Tromsø, Norway.
Eur J Orthod. 2015 Apr;37(2):128-34. doi: 10.1093/ejo/cju014. Epub 2014 Jul 8.
The eruption guidance appliance (EGA) aims to correct sagittal and vertical occlusal relations concomitantly with alignment of the incisors. Few reports have been published on treatment effects with the EGA but no randomized studies have been available.
The aim was to find out if 1 year active treatment time with EGA was sufficient for achieving normal occlusal relationships and dental alignment in 7- to 8-year-old children.
PARTICIPANTS, STUDY DESIGN, AND METHODS: Eligibility criteria for participants were: fully erupted upper central incisors, and Angle's Class I or Class II molar relationship combined with any of the following traits: deep bite, increased overjet ≥5mm, moderate anterior crowding with overjet ≥4mm. After screening of 148 children, 48 7- to 8-year-old children were recruited in the study. The participants were randomly assigned into a treatment group (N = 25) and a control group (N = 23). Children in the treatment group received treatment with the EGA for 1 year. The controls had no orthodontic treatment. Changes in overjet, overbite, Angle's Class, and crowding were used as primary outcome measures. Occlusal assessments were performed on dental casts obtained from all subjects at start of the study (T1) and after 1 year (T2). Lateral cephalograms were obtained from all subjects at T1 and from the treatment group at T2. All measurements on dental casts and cephalograms were carried out blinded.
Forty-six children completed the study. Mean overjet and overbite decreased significantly in the treated subjects during 1 year, in contrast to a slight increase in the controls. Class II molar relationship decreased from 46 to 4 per cent in the treatment group, with no significant change in the control group. Mandibular anterior crowding decreased significantly in the treated subjects, while the controls showed a slight increase.
In short term, the EGA seems to be effective in correcting increased overjet and overbite, Class II malocclusion, and lower anterior crowding in the early mixed dentition. Follow-up data are needed to assess long-term effects of this treatment.
This study was not registered.
萌出引导矫治器（EGA）旨在矫正矢状向和垂直向咬合关系，同时排齐切牙。关于EGA治疗效果的报道较少，且尚无随机研究。
旨在探究对7至8岁儿童进行1年的EGA积极治疗时间是否足以实现正常的咬合关系和牙齿排齐。
参与者、研究设计与方法：参与者的纳入标准为：上颌中切牙完全萌出，安氏I类或II类磨牙关系，并伴有以下任何一种特征：深覆合、覆盖增加≥5mm、伴有覆盖≥4mm的中度前牙拥挤。在对148名儿童进行筛查后，48名7至8岁儿童被纳入研究。参与者被随机分为治疗组（N = 25）和对照组（N = 23）。治疗组儿童接受EGA治疗1年。对照组未接受正畸治疗。覆盖、覆合、安氏分类和拥挤度的变化用作主要观察指标。在研究开始时（T1）和1年后（T2），对所有受试者制取的石膏模型进行咬合评估。在T1时对所有受试者以及在T2时对治疗组获取头颅侧位片。对石膏模型和头颅侧位片的所有测量均在盲法下进行。
46名儿童完成了研究。在1年期间，治疗组受试者的平均覆盖和覆合显著降低，而对照组则略有增加。治疗组II类磨牙关系从46%降至4%，对照组无显著变化。治疗组受试者下颌前牙拥挤显著降低，而对照组略有增加。
短期内，EGA似乎对矫正混合牙列早期增加的覆盖和覆合、II类错合以及下前牙拥挤有效。需要随访数据来评估该治疗的长期效果。
本研究未注册。
