Modified Quadrangular Le Fort I Osteotomy for Maxillary Advancement

Objectives: Conventional Le Fort I osteotomy (LFI) has limitations to the advancement of the midface. In an earlier study, we modified the quadrangular Le Fort I osteotomy procedure, to include anterior quadrangular osteotomy and posterior horizontal osteotomy. This study was aimed at evaluating the clinical outcome of the modified Quadrangular Le Fort I osteotomy (MQLI) in maxillary retrusion.

Materials and Methods: A total of 40 patients who had undergone maxillary advancement were included in this study. MQLI patients (n = 20) were compared with LFI patients (n = 20) using cephalometric radiographs taken preoperatively (T0), postoperatively (T1), and 6 months postoperatively (T2). The reference point C0 was the point of intersection of the soft tissue outline of the cheek (cheek line) and the horizontal reference plane (FH plane). Points C1–C4 were defined as points of intersection of the cheek line and lines drawn parallel and inferior to the horizontal reference plane (FH plane) at 5 mm intervals, beginning with point C1, positioned 15 mm below the FH plane. Soft tissue radiographic changes of the cheek line (C1–C5), profile of the nose, and skeletal movements were analyzed.

Results: The maxilla moved anteriorly by 3.0 ± 1.0 mm in the LFI group and 3.5 ± 2.8 mm in the MQLI group. The amount of mandibular setback was 12.3 mm in the LFI group, whereas it was 13.0 mm in the MQLI group (p > 0.05). Infraorbital soft tissue cheek outline which was inferior to the infraorbital landmark significantly moved anteriorly (T2-T0: C4: 2.7 mm, C5: 2.9 mm; p < 0.05) in MQLI patients, whereas the LFI patients did not show significant difference (T2-T0: C4 2.0 mm, C5 2.2 mm; p > 0.05). Overall, the soft tissue cheek outline moved anteriorly in MQLI, but this change was not significantly different from that with LFI. MQLI showed skeletal stability similar to that by LFI at B point (T2-T1: MQLI 1.8 mm, LFI 1.0 mm; p > 0.05).

Conclusion: MQLI can be an efficient surgical method to advance the maxilla and infraorbital area with acceptable stability.

Ref)

Keller EE, Sather AH. Quadrangular Le Fort I osteotomy: surgical technique and review of 54 patients. J Oral Maxillofac Surg. 1990;48:2-11.

Abubaker AO, Sotereanos GC. Modified Le Fort I (maxillary-zygomatic) osteotomy: rationale, basis, and surgical technique. J Oral Maxillofac Surg. 1991;49:1089-97.