Objective: To analysis the maxillary bony structures by three-dimensional CT in maxillary retrognathism patients so as to provide information for Le Fort I osteotomy.
Methods: 20 maxillary retrognathism patients underwent Le Fort I osteotomy, while 20 patients with simple mandibular fractures were included as control group. All the patients received Skull 3-D CT before operation. The measurement about descending palatine artery and wing palatal was performed by Surgicase 5.0. The data were analyzed statistically.
Results: The average distance from the piriform aperture margin to wing palatal tube was (33.74 +/- 6.74) mm in the retrognathism group; while (35.67 +/- 7.50) mm in the control group, showing a significant difference between the two groups (P < 0.05), but there was no statistically difference in the height of pterygomaxillary junction between the two groups.
Conclusion: The safe depth for Le Fort I osteotomy in patients with hypoplasia maxilla is 32 mm. CT scanning can provide guidance for osteotomy.