VERTICAL AND HORIZONTAL STABILITY FOLLOWING LE FORT I OSTEOTOMY WITHOUT BONE GRAFT

objectives: the study aimed to evaluate the vertical and horizontal stability following Le Fort I osteotomy without using any bone graft in patients with maxillary advancement up to 6 mm alone or combined with vertical repositioning.
Patients and methods: patients referred for one piece Le Fort I osteotomy with or without other orthognathic procedures were included in this study. In all surgeries, the maxilla was fixed using titanium plates and no bone graft was used in any of the patients. Suspension wires were fixed to be used for IMF with elastics postoperatively. Lateral cephalometric X-rays were taken 1 week after the surgery (T1), and 1 year after the surgery (T2), these X-rays were used to evaluate the postoperative stability using the SNA angle, maxillary depth angle, palatal plane angle, and maxillary height angle to evaluate changes in the horizontal and vertical direction.
 
results: The lateral cephalometric analysis for relapse in the anteroposterior direction showed that only 6 patients out of 18 (33.3%) encountered a relapse of more than 2° in SNA angle and 5 (27.7%) in the maxillary depth angle measurements. Yet in between those patients there was only one (5.5%) out of 18 patients had only maxillary advancement without vertical repositioning. The results of the maxillary height and palatal plane angles showed that all the changes of more than 2° in the vertical direction were in the elongation group (3 patients out of four) (75%) using the palatal plane angle while it was only 1 patient (25%) using the maxillary height angle evaluation. Conclusion: within the limitation of the present study (small sample number especially in the patients with vertical repositioning) ; the study suggests that the use of bone graft can be avoided in maxillary advancement movement up to 6 mm anterior repositioning even this was combined with superior repositioning. Moreover the study recommends the use of bone graft in cases of anterior maxillary advancement with inferior repositioning of the maxilla.