Rapid maxillary expansion effects on dynamic measurement of natural head position

Angle Orthod. 2011 Sep;81(5):850-5. doi: 10.2319/112410-686.1. Epub 2011 Mar 14.


Objective: To identify the effect of rapid maxillary expansion (RME) procedure on dynamic measurement of natural head position (NHP).

Materials and 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.

Conclusion: Treatment with the RME procedure showed no statistically significant effects on dynamic measurement of NHP when compared with initial values or untreated control.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cephalometry
  • Child
  • Female
  • Head / anatomy & histology*
  • Humans
  • Male
  • Mandible / pathology
  • Maxilla / pathology
  • Nasal Bone / pathology
  • Nose / physiology
  • Orthodontic Appliance Design
  • Palatal Expansion Technique* / instrumentation
  • Posture
  • Respiration
  • Sella Turcica / pathology
  • Time Factors