International audienceWe 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