[Using three-dimensional CT to guide Le Fort I osteotomy in maxillary retrognathism patients].

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.