A METHOD FOR TRUE COORDINATE 3-DIMENSIONAL MEASUREMENT OF CASTS USINGA MEASURING MICROSCOPE

Exact 3-dimensional measurements are more useful for researchers and c linicians than are relative distance measurements. Through the use of a measuring microscope and a personal computer, the technique presente d in this article provides meaningful and accurate (0.005 mm) 3-dimens ional measurements of casts in true coordinates (x, y, z). By fabricat ing the master cast with reference landmarks, leveling the casts befor e measurement, removing the cast between repeat measures, and mathemat ically rotating the data points, this technique places all the landmar ks in a standardized reference plane that allows for the comparison of dimensional changes between different casts.