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Coupled hard–soft tissue simulation with contact and constraints applied to jaw–tongue–hyoid dynamics

We present an open‐source physical simulation system suitable for efficient modeling of anatomical structures composed of both hard and soft tissue components, interconnected by point‐wise attachments, contact, and other constraints. Specific attention is paid to the computational formulation needed for the coupled simulation of rigid and deformable structures, and a constraint‐based mechanism is described for attaching these together. As an application of this system, we then present a novel 3D dynamic model of the jaw–tongue–hyoid complex, consisting of an FEM model of the tongue, rigid jaw, and hyoid structures, point‐to‐point muscle actuators, and constraints for bite contact and the temporomandibular joints. Several simulations are presented showing combined jaw–tongue actions and demonstrating the effects of coupled jaw–tongue–hyoid dynamics. Copyright © 2010 John Wiley & Sons, Ltd.