The long-term effect of maxillary advancement and impaction on subjective and objective nasal patency: A retrospective case-control study.

The aim of this study was to investigate the change of nasal patency after maxillary advancement and impaction (MAXADV + IMP) in subjects with skeletal class III malocclusion (cases) and after removal of maxillary cysts in close proximity to the nasal floor in subjects that served as controls. NOSE score, volume derived by computed tomography (VOL), and acoustic rhinometry and rhinomanometry were retrospectively evaluated, before and one year after surgery. The movement of specific landmarks was also measured. NOSE score did not change after surgery, neither in 17 cases (p = 0.10) nor in 17 controls (p = 0.14). In cases, VOLpostop (10088 ± 4200 mm3) was significantly higher than VOLpreop (7807 ± 3721 mm3; p = 0.036). Maxillary advancement and inferior displacement of the ventral maxilla were noted by the movement of incisive foramen in the coronal (3.9 ± 5.4; p = 0.011) and Frankfurt Horizontal plane (2.2 ± 2.0; p = 0.001), respectively. In controls, VOLpostop (9749 ± 3654 mm3) was also significantly higher than VOLpreop (8473 ± 2624 mm3; p = 0.050). Cross-sectional areas, nasal flow and nasal resistance changed significantly after surgery in cases (6/30 pairs; p < 0.018), but not in controls (all p > 0.066). MAXADV + IMP increased nasal patency, but did not change the feeling of nasal breathing. Physicians should proceed with caution when informing patients about improvement of nasal breathing after MAXADV + IMP.