title: One year treatment effects of the eruption guidance appliance in 7- to 8-year-old children: a randomized clinical trial.
abstract: BACKGROUND
  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.
  
  
  OBJECTIVE
  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.
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
  
  
  BACKGROUND
  This study was not registered.
authors.affiliation: *Institute of Clinical Dentistry, Faculty of Health Sciences, University of Tromsø, Norway, rita.myrlund@tromsfylke.no.
authors.forename: Rita
authors.initials: R
authors.lastname: Myrlund
authors.affiliation: *Institute of Clinical Dentistry, Faculty of Health Sciences, University of Tromsø, Norway.
authors.forename: Mari
authors.initials: M
authors.lastname: Dubland
authors.affiliation: **Department of Oral and Maxillofacial Diseases, Vaasa Central Hospital, Finland.
authors.forename: Katri
authors.initials: K
authors.lastname: Keski-Nisula
authors.affiliation: *Institute of Clinical Dentistry, Faculty of Health Sciences, University of Tromsø, Norway.
authors.forename: Heidi
authors.initials: H
authors.lastname: Kerosuo
mesh_terms: D002508:Cephalometry / Q000379:methods; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008310:Malocclusion / Q000628:therapy*; D008311:Malocclusion, Angle Class I / Q000628:therapy; D008312:Malocclusion, Angle Class II / Q000628:therapy; D008334:Mandible / Q000254:growth & development; D017289:Orthodontic Appliances, Functional; D009972:Orthodontics, Interceptive / Q000295:instrumentation / Q000379:methods; D057887:Overbite / Q000628:therapy; D014078:Tooth Eruption