A Dynamic Jaw Model With a Finite-Element Temporomandibular Joint

Area of Science:

• Biomechanics
• Computational modeling
• Human orofacial system

Background:

• Temporomandibular disorders (TMDs) are linked to temporomandibular joint (TMJ) stress.
• Direct in vivo measurement of TMJ forces is not feasible.
• Biomechanical computer simulation is crucial for investigating the masticatory system.

Purpose of the Study:

• To develop a novel, dynamic computer model of the masticatory system.
• To investigate TMJ biomechanics and joint stresses during various tasks.
• To validate the model using high-resolution MRI data.

Main Methods:

• A muscle-driven rigid body model of the jaw was combined with a finite element model (FEM) of the disk and elastic foundation (EF) articular cartilage.
• The model was validated against MRI data of mandibular protrusion and opening.
• Joint stresses were computed for clenching, protrusion, and opening movements.

Main Results:

• Simulated mandibular and disk positions/shapes closely matched MRI data.
• The model generated plausible disk stress patterns for dynamic tasks.
• A novel contact model combining EF layers and FEM body significantly reduced computation time.

Conclusions:

• The developed dynamic computer model is a valuable tool for TMJ investigation.
• This model can enhance understanding of the masticatory system and TMD-related joint stress.
• It may aid in identifying therapeutic approaches for orofacial function restoration.