After the shape of the zone of implantation in the mouth is obtained by direct impression, micro-sensing or optical impression, a prosthesis or a mold for making a prosthesis is automatically machined by machine tool at a work center with the assistance of a calculator or computer which takes into consideration...http://www.google.ca/patents/US5092022?utm_source=gb-gplus-sharePatent US5092022 - Method of producing a dental prosthesis
