On the improvement of nasal breathing following mid-face osteotomies, and possible reasons for the phenomenon.

In the great majority of patients with hypoplasia of the middle third of the face, the surgical advancement or displacement of the maxilla results in a subjective improvement in nasal breathing, which can also be verified. This is due to an increase in the volume of the nasal skeleton and/or in the nasolabial angle, which improves nasal ventilation. These operations have virtually no effect on endonasal obstructions to flow, which, in order further to improve nasal breathing, should be dealt with separately.