Measuring the accuracy of various elastomeric impression materials using a CNC coordinate measuring device (Part 1)
Wichmann, M.; Borchers, L.; Limmroth, E.
Deutsche Zahnarztliche Zeitschrift 45(8): 499-502
1990
ISSN/ISBN: 0012-1029 PMID: 2269183 Document Number: 360152
This study compares the accuracy of 23 impression materials. With each material seven impressions of a stainless steel master die were taken under standardized conditions. Characteristical dimensions of the master die and of the stone dies as well were determined by means of a CNC coordinate measuring device. Differences in prepared tooth heights ranged between -36 and +19 microns. The occlusal distances between prepared teeth were 2 to 54 microns greater on the stone dies than on the master die. Diameters differed by -89 to +52 microns. The two phase impressions tended to result in stone dies of reduced size, whereas single phase and double mix impression techniques produced larger stone dies than the master die.