Effects Of Rapid Maxillary Expansion On Upper Airway PDF Download

Introduction: This analysis is part of an ongoing retrospective secondary pilot study on a randomized clinical trial. The purpose of this research project was to evaluate the effect of none-surgical maxillary expansion techniques on upper airway dimension and function, and skeletal and dental changes, using two different maxillary expanders: Moon and Dresden expanders. Methods: A sample of thirteen patients were randomly allocated to either group A or group B. Patients in group A (N=5) received orthodontic treatment using an appliance called Dresden expander. Patients in group B (N=8) received orthodontic treatment using the Moon expander. Two sets of records were taken for each patient; before starting treatment (T0) and after maxillary expansion completed (T1). Records consisted of the following: clinical charting and diagnostic exams, intra-oral and extraoral photos, cone beam computer tomography (CBCT), nasal obstruction symptom evaluation (NOSE) questionnaires, and peak nasal inspiratory flow (PNIF). The changes on the upper airway dimension and function were evaluated using CBCT scans (using Dolphin software), PNIF (objective measurement), and NOSE questionnaire (subjective measure). The skeletal and dental changes were evaluated using various skeletal and dental landmarks in CBCT using Avizo software. For upper airway changes and skeletal and dental changes, one-way repeated measure mixed ANOVA tests and paired sample t-tests were conducted. Results: For upper airway changes, from T0 to T1, no statistically significant differences were found between the Moon and the Dresden expander groups for nasopharynx volume (NPV), oropharynx volume (OPV), oropharynx minimal cross-sectional area (OPMCA), PNIF with both nostrils (PNIFBN), PNIF with left nostril blocked (PNIFLB), and PNIF with right nostril blocked (PNIFRB), and NOSE questionnaires. Also, both expanders showed to have no significant effect on upper airway dimensions and function. For skeletal and dental changes, Moon expander resulted in buccal displacement of pulp chamber of tooth # 1.6, 2.6, and 2.4 (p0.05). Conclusion: The effect of microimplant-assisted rapid palatal expansion (MARPE) appliances on upper airway dimension and function in adults is yet to be determined and future randomized controlled clinical trial studies with larger sample size are needed. In terms of skeletal and dental changes, the only statistically significant change was in the Moon expander group in transverse (X) direction for pulp chamber of upper first molars and upper left first premolar. However, such changes may not be clinically significant. No significant differences were found between the two appliance designs in this analysis.