Abstract: A device useful in demonstrating occlusion and the effect thereof on the temporomandibular joint can be constructed so as to use an upper member shaped so that portions of it simulate a maxilla, maxillary teeth and a fossa and so as to use a lower member shaped so that portions of it simulate a mandible, mandibular teeth and a condyle. The lower member is held with respect to the upper member through the use of a plurality of resilient members in such a manner that the condyle is within the fossa and is movable with respect to it and in such a manner that the two sets of simulated teeth are adjacent to one another. The condyle is smaller than the fossa so at to permit it to be moved generally within the fossa as the lower member is moved relative to the upper member in demonstrating occlusion between various different types of teeth.