In vitro comparison of fixation techniques for stabilization of Le Fort I osteotomy in short and large advancements of the maxilla.

PURPOSE: Le Fort I osteotomy is widely performed in orthognathic surgery for maxillary repositioning and for the treatment of dentofacial deformities and obstructive sleep apnea (OSA). Postoperative relapse remains a concern, particularly after large maxillary advancements, highlighting the importance of rigid fixation. This study aimed to determine which fixation technique provides the greatest rigidity.

METHODS

In this in vitro study, the biomechanical rigidity of five commonly used fixation techniques for Le Fort I osteotomies was evaluated using 150 polyurethane specimens with advancements of 5 mm and 10 mm. The techniques included two L-plates (A), four L-plates of different thicknesses (B and C), two precontoured Le Fort I plates (D), and a hybrid configuration with two precontoured Le Fort I plates combined with two L-plates (E). Resistance to vertical displacement was measured at 1, 3, and 5 mm using a biomechanical testing machine.

RESULTS

Fixation E consistently showed the highest resistance across both advancement distances and all displacement intervals, significantly outperforming fixations A, C, and D. Fixation B demonstrated resistance comparable to fixation E, whereas fixation C showed inferior performance despite a similar configuration. Fixations A and D showed the lowest resistance, particularly at 10 mm advancement.

CONCLUSION

Overall, fixation E provided the greatest rigidity, while techniques relying on only two plates were biomechanically less effective. Further clinical studies are required to determine the clinical relevance of these findings.