Examination of the test for compressive strength applied to zinc oxide eugenol cements.

The distribution of compressive strength results for a zinc oxide eugenol cement is negatively skewed. However, removal of a small number of outlying low results converts the distribution to a normal one. Crosshead speed and friction at the anvil have no significant effect on results, but compressive strength is a function of the diameter-length ratio of the cylinder and increases with this ratio.