Biomechanical evaluation of fixation techniques for bridging segmental mandibular defects

Area of Science:

• Biomedical Engineering
• Oral and Maxillofacial Surgery
• Materials Science

Background:

• Segmental mandibular defects require reconstruction using rigid fixation devices.
• Evaluating the biomechanical properties of available plating systems is crucial for optimal clinical outcomes.

Purpose of the Study:

• To compare the biomechanical properties of three distinct mandibular reconstruction plating systems.
• To assess the performance of locking and non-locking plate designs under load.

Main Methods:

• A controlled in vitro study using polyurethane mandibles with simulated segmental defects.
• Four groups were tested: three with different reconstruction plates (3.0-mm locking-screw, 2.4-mm low-profile, 2.4-mm standard) and one control group.
• Load-to-failure and fatigue testing were conducted to quantify yield displacement, yield load, bending stiffness, and cycles to failure.

Main Results:

• All tested plating systems demonstrated comparable biomechanical integrity in single load-to-failure tests.
• The 3.0-mm locking-screw and 2.4-mm low-profile plates exhibited significantly greater fatigue resistance compared to the control.
• The standard 2.4-mm plate also showed improved fatigue performance over the control group.

Conclusions:

• All evaluated mandibular fixation systems provide adequate biomechanical stability for defect reconstruction.
• Higher-profile plating designs may offer superior fatigue performance.
• Locking and non-locking designs performed similarly, with no screw-substrate interface failures observed.