To allow a high-accuracy positioning and facilitate the re-mounting on an articulator by using a positioning member used for setting upper jaw and lower jaw mouth cavity models to the articulator as a positioning member used for a three-dimensional shape measuring device.

When a three-dimensional shape measuring device is installed after upper jaw and lower jaw mouth cavity models are mounted on an articulator and removed, an upper jaw frame 21 is rotated upward, an incisory pin 25 and an incisory table 26 are separated, then both mouth cavity models 5, 7 and a three-dimensional shape measuring auxiliary device 10 are integrally removed. The positioning pin of a measured object mount base and the coupling holes 2a, 2b of the second mouth cavity model fixing base 2 are coupled for the positioning in the horizontal direction. The positioning in the vertical direction is conducted by the upper face of the measured object mount base and the reference face 2d of the second mouth cavity model fixing base 2, and three-dimensional shape measurement is conducted by a probe such as a laser displacement gauge.