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.