Abstract: The present invention is concerned with apparatus and methods in the field of dentistry and in the field of design and testing of dental fixtures, components and materials. The apparatus comprises a jaw model having a mandible and a maxilla; a loading mechanism, coupled to the jaw model, for imposing an occlusal force on the mandible and maxilla; a mechanism(s), coupled to the mandible of the jaw model, for moving the mandible relative to the maxilla; and a load or force sensing device for sensing occlusal forces on the mandible and the maxilla of the jaw model. The mandible is caused to move laterally and protrusively using electric motors. A strain gauge meter may be coupled to the load sensing device, for measuring and displaying the forces sensed by the sensing device. A digital processor may also be employed for storing and recording the forces measured by the meter.

Abstract: A radiation pyrometer has four rectangular photodiodes mounted in an orthogonal array. Radiation from a hot body is focussed as a circular image centrally of the array. The outputs of diagonally opposite photodiodes are connected together to form two identical output channels.