Process for producing endoprostheses

摘要

PCT No. PCT/EP94/04020 Sec. 371 Date Aug. 5, 1996 Sec. 102(e) Date Aug. 5, 1996 PCT Filed Dec. 2, 1994 PCT Pub. No. WO95/15131 PCT Pub. Date Jun. 8, 1995A process for producing endoprosthesis has the data block of a three-dimensional actual model (10) of the existing bone structure of a patient acquired using CT scanning. In a computer the actual model (10) thus determined is subtracted from the data block of an existing or CT scan-generated three-dimensional reference model (14). Then from the difference a computer-internal model for the endoprosthesis is formed. With this process, it is possible to reduce the work required for making the corrective adaptation of the endoprosthesis and to avoid faulty adaptations. The data blocks of the actual model (10) and reference model (14) are converted into the data of a CAD free form surface geometry. This is done by describing the limiting surfaces of the models through Spline and Bezier functions oriented to points of support and are imaged, and superimposed, on the computer monitor. This imaging is used to take back segments of the interface (11) of the actual model (10) by displacing points of support toward the volume of the reference model (14).