Virtual jaw: a 3D simulation for computer assisted surgery and education.

The jaw is one of the most complex joints in the human body. Its sliding and gliding movements are difficult to understand. Therefore, up to now there exist only mechanical simulations. But there is a strong need for a computer model of the jaw--the virtual jaw--to support physicians and surgeons in diagnoses and preoperative planning. During the preoperative planning of craniofacial operations for example, individual patient data has to be examined and the operation has to be simulated. In the education of physicians such a simulation system gives a much better understanding of the anatomy and functionality of the jaw than static images in text books do. The paper presents a 3D simulation of the human mastication apparatus which can be used for the preoperative planning of craniofacial surgeries as well as the education of dentists and surgeons. It consists of three interacting components: A kinematic model which defines the constraints of the articulation, a model for the mastication muscles and a 3D graphical interface.