Does Maxillomandibular Fixation Technique Affect Occlusion Quality in Segmental LeFort I Osteotomy?

Area of Science:

• Oral and Maxillofacial Surgery
• Orthodontics
• Biomedical Engineering

Background:

• Segmental maxillary osteotomies demand precise occlusal control due to segment positioning variability.
• The effectiveness of different maxillomandibular fixation (MMF) techniques in achieving occlusal control remains unvalidated.

Purpose of the Study:

• To quantitatively assess and compare the accuracy of occlusal positioning across various MMF techniques.
• To determine which MMF technique offers the best occlusal control in simulated LeFort I osteotomies.

Main Methods:

• A double-blinded in vitro study utilized experimental models simulating a 3-piece LeFort I osteotomy.
• Three distinct MMF techniques (brackets, MMF screws, embrasure wires) were applied to 32 models each, with outcomes compared to baseline.
• Occlusal accuracy was evaluated using visual occlusal analysis scores (VAOS) and linear occlusal error measurements.

Main Results:

• Brackets demonstrated significantly higher VAOS (median differences 1.49 and 0.48, P < .001) compared to MMF screws and embrasure wires.
• Models using brackets exhibited lower linear occlusal errors (median differences 0.35–0.99 mm, P < .001) than those with MMF screws or embrasure wires.
• A VAOS of 3.50 was established as the accuracy threshold, with brackets exceeding this more consistently.

Conclusions:

• The choice of MMF technique critically influences the precision of occlusal control in segmental maxillary surgery.
• Brackets offer superior occlusal accuracy and reduced linear error compared to MMF screws and embrasure wires.
• These findings are relevant for optimizing surgical planning and execution in complex maxillofacial reconstructions.