1. A method of producing a dental prosthesis which comprises, carrying out under the control of a computer the steps of: creating an interference pattern containing site data corresponding to a three-dimensional view of a site in the buccal cavity; scanning said interference pattern to produce digital site data; processing said digital site data to create machine tool data; machining said prosthesis to fit said site and said buccal cavity directly under control of said machine tool data, said computer having a memory having a plurality of standard tooth patterns stored therein; and wherein said step of processing said digital site data comprises generating an envelope enclosing the volume of said prosthesis from said digital site data, displaying the so-produced envelope, selecting from said plurality of standard tooth patterns the pattern corresponding most closely to said organ, displaying the so-selected tooth pattern, and fitting said tooth pattern into said envelope under operator control, thereby creating a desired shape display, and wherein said computer computes said machine tool data based on said selected standard tooth shape as modified to create said desired shape display.