A finite element analysis for evaluating mandibular advancement devices

Area of Science:

• Biomedical Engineering
• Dental Mechanics
• Sleep Medicine

Background:

• Obstructive sleep apnoea (OSA) involves upper airway collapse during sleep.
• Mandibular advancement devices (MADs) are effective OSA treatments, repositioning the mandible to enlarge the airway.
• Long-term MAD use can cause adverse effects on teeth and periodontal ligaments.

Purpose of the Study:

• To evaluate the biomechanical effects of MADs on teeth and periodontal ligaments using a finite element model.
• To analyze how variations in MAD design, force application, and material influence tooth displacement and stress.
• To compare the load distribution of different MAD connection mechanisms.

Main Methods:

• Developed a finite element model of the human jaw and teeth.
• Utilized Reverse Engineering from tomographic images and laser scans of a physical MAD.
• Simulated MAD forces with varying design parameters (connection mechanism, material, force application point).

Main Results:

• The finite element model predicted tooth displacement and stress patterns under simulated MAD forces.
• A central connection mechanism was found to concentrate stress primarily on anterior teeth.
• A lateral connection mechanism demonstrated a more uniform distribution of mechanical load across the teeth.

Conclusions:

• MAD design significantly influences biomechanical outcomes on the stomatognathic system.
• Lateral connection mechanisms in MADs may offer a more favorable load distribution, potentially reducing adverse effects on teeth and periodontal tissues.
• Finite element modeling is a valuable tool for optimizing MAD design for OSA treatment.