Abstract: An apparatus and process for use in preparing a crown portion to be affixed on a tooth stump is described. A model of the tooth stump is clamped to remain immobile and scanned with a scanning head attached to a numerically controlled processing machine. Data from the scanning head indicative of the contour of the tooth stump is stored in a computer memory. From this data a contour for a casting model used to make a crown portion is calculated and stored in the computer memory. Molding material, such as wax, is placed on the tooth stump and a contour tool attached to the numerically controlled processing machine processes the molding material to produce the casting model using the calculated data. The casting model may then be used to produce a crown portion which may be further finished with a contour tool coupled to the numerically controlled processing machine using the calculated data from the computer memory.

Abstract: To reproduce jaw movements, electric distance measuring devices are fixed at the lower jaw and the upper jaw in the mouth of a patient to measure, with relative movements between upper and lower jaws, the distances between defined points of the two jaws and to supply the data to a memory. In accordance with the recorded measuring data a mobile portion of an articulator carrying a jaw model is so guided that it reproduces the recorded sequence of motion, the combinations of the measured distances between the defined points of lower jaw and upper jaw being repeated in the same way as in the measuring operation.