A new system for custom helical mandibular distraction: a bench study on anatomical models

Area of Science:

• Biomedical Engineering
• Craniofacial Surgery
• Orthognathic Surgery

Background:

• Current mandibular distraction osteogenesis (DO) devices are limited to rectilinear or simple circular movements.
• Existing stock or hybrid distractors may not achieve optimal mandibular repositioning for complex deformities.

Purpose of the Study:

• To evaluate the accuracy of a novel patient-specific helical distractor.
• To compare its performance against commonly used rectilinear and hybrid devices in mandibular DO.

Main Methods:

• Bench feasibility study using 3D-printed models from four patients with severe mandibular deformities.
• Computer-assisted surgical simulation to plan distraction paths for helical, hybrid, and stock distractors.
• Comparison of post-distraction model accuracy against planned treatments via landmark registration.

Main Results:

• Helical distractors achieved the lowest median landmark misalignment (1.8 mm) compared to hybrid (3.3 mm) and stock (3.6 mm) devices.
• Helical devices also resulted in superior occlusal alignment (0.6 mm) versus hybrid (1.0 mm) and stock (0.95 mm).
• No significant accuracy difference was observed between hybrid and stock distractors.

Conclusions:

• Patient-specific helical distractors demonstrate superior accuracy in achieving planned mandibular positioning during DO.
• This novel device represents a promising advancement for improving outcomes in mandibular reconstruction and deformity correction.
• Further clinical validation in larger patient cohorts is recommended.