title: Rapid maxillary expansion effects on dynamic measurement of natural head position.
abstract: OBJECTIVE
  To identify the effect of rapid maxillary expansion (RME) procedure on dynamic measurement of natural head position (NHP).
  
  
  METHODS
  The treatment group comprised 23 patients, 12 girls and 11 boys (mean age: 10.1 ± 1.1 years), and the control group comprised 15 subjects, 8 girls and 7 boys (mean age: 9.7 ± 1.4 years). The test subjects underwent RME treatment using full cap acrylic device, and the mean amount of expansion was 5.48 mm. An inclinometer and a portable data logger were used to collect the NHP data. Intragroup changes were evaluated by using nonparametric Wilcoxon test, and intergroup changes were analyzed with Mann-Whitney U-test. P values less than .05 were considered statistically significant.
  
  
  RESULTS
  The mean difference between initial and final NHP was 0.31°, and this difference was not statistically significant. Also, there were no statistically significant differences between the RME and control groups before and after treatment.
  
  
  CONCLUSIONS
  Treatment with the RME procedure showed no statistically significant effects on dynamic measurement of NHP when compared with initial values or untreated control.
authors.affiliation: Erciyes University, Faculty of Dentistry, Department of Orthodontics, Kayseri, Turkey.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Yagci
authors.forename: Tancan
authors.initials: T
authors.lastname: Uysal
authors.forename: Serdar
authors.initials: S
authors.lastname: Usumez
authors.forename: Metin
authors.initials: M
authors.lastname: Orhan
mesh_terms: D002508:Cephalometry; D002648:Child; D005260:Female; D006257:Head / Q000033:anatomy & histology*; D006801:Humans; D008297:Male; D008334:Mandible / Q000473:pathology; D008437:Maxilla / Q000473:pathology; D009295:Nasal Bone / Q000473:pathology; D009666:Nose / Q000502:physiology; D016382:Orthodontic Appliance Design; D010155:Palatal Expansion Technique / Q000295:instrumentation; D011187:Posture; D012119:Respiration; D012658:Sella Turcica / Q000473:pathology; D013997:Time Factors