[The stereognathograph PC--test results with the new version of the device]

The PC stereognathograph was investigated for measurement errors in laboratory experiments on an optical bench as well as on an articulator. The values obtained were compared with the data of the predecessor model. A substantial reduction in the linearity in transverse measurements has been effected, so that these are now within acceptable limits. A variation of linearity factors which can be avoided by electronic fine adjustment still arises owing to incongruence of the six measurement channels. The hinge axis can be localized very well on the articulator. By and large, the announced correction of the projection error which we have demanded has not been implemented up to now. In view of the clear imaging of condylar movement in space and time on the monitor and the adequate precision of the clinical measurements effected, the PC stereognathograph appears to be a valuable system for instrumental diagnostics.