Does rapid maxillary expansion increase nasopharyngeal space and improve nasal airway resistance?

OBJECTIVE

To evaluate the effect of rapid maxillary expansion (RME) on the dimension of the nasopharyngeal space and its relation to nasal airway resistance.

METHODS

Twenty-five school-age children (from 7 to 10 year-old) with mouth and/or mixed breathing, with mixed dentition and uni- or bilateral posterior crossbite involving the deciduous canines and the first permanent molars, were evaluated. RME was placed and remained during 90 days. Rhinomanometry and orthodontic documentation were performed at four different times, i.e., before (T(1)), immediately after (T(2)), 90 days (T(3)) and 30 months (T(4)) after RME.

RESULTS

Differences in nasopharyngeal area and in nasal airway resistance were observed only 30 months after RME, and could be explained by facial growth, and not because of the orthodontic procedure.

CONCLUSION

RME does not influence on nasopharyngeal area or nasal airway resistance in long-term evaluation.