The nasal airway following maxillary expansion.

There have been suggestions that maxillary expansion may be justified on the basis of airway considerations alone. The present study assessed the effects of rapid maxillary expansion and surgical expansion on nasal airway size to determine how useful these techniques are for breathing purposes. The results demonstrate that both procedures generally improve the nasal airway. However, approximately one third of the subjects in both groups did not achieve enough improvement to eliminate the probability of obligatory mouth breathing. These findings suggest that maxillary expansion for airway purposes alone is not justified.