Surgical accuracy in Le Fort I maxillary osteotomies

The surgical outcome of planned movements of Le Fort I osteotomies is dependent on the surgeon's ability to achieve such movements intraoperatively. Our aim was to assess the surgical accuracy achieved for 30 consecutive patients undergoing Le Fort I osteotomies treated by one maxillofacial surgeon and his team.

Intraoperative control of the mobilized maxilla vertically was achieved by a combination of a nasion screw as the external reference point and bony marks above and below the osteotomy cuts intraorally. Movements horizontally and transversely were controlled with occlusal wafers. The surgical accuracy of maxillary movements vertically and horizontally (anteroposteriorly) were assessed by standard lateral cephalometric tracings of radiographs taken within two weeks prior to operation and 48 hours afterwards. Audit targets were arbitrarily set to be satisfactory when the difference between planned movements and actual movements as measured on the cephalometric tracings were 2 mm or less.

The mean (SD) difference from planned vertical movements of the anterior maxilla was 0.37 mm (SD 0.64) and horizontal movements 0.85 mm (SD 0.91). Ninety-seven percent (29/30) of anterior maxillary movements in the vertical dimension, 90% (27/30) of anterior maxillary movements in the horizontal dimension and 87% (26/30) of movements in both dimensions had a difference of 2 mm or less. These results were comparable with the reported 'gold standard'.

Good surgical accuracy in positioning the mobilized maxilla in Le Fort I osteotomies can be achieved with the use of external and internal reference points.