Introduction: There are distinct effects on nasal morphology after various movements of the maxilla in Le Fort-1 osteotomies. Corresponding change in nasal volume may have important surgical and anaesthetic implications. Some movements such as superior repositioning of the maxilla may have a significant influence on nasal airflow. The purpose of our study was to investigate the effect of maxillary Le-Fort 1 impaction, advancement or a combination of both on nasal airflow before and after Le Fort-1 osteotomy.