Evaluation of Cure Depth and Geometrical Overgrowth Depending on Zirconia Volume Fraction Using Digital Light Processing.

The optical properties of zirconia photopolymer suspension for DLP (Digital Light Processing) were evaluated. The light source and intensity were set to 395 nm and 30 mW/cm². Experimental groups were divided into 48, 50, 52, 54, 56 and 58 vol% according to the zirconia volume fraction. The cure depth of all groups was at least 47.35 um when cured for 1 sec, which was higher than layer parameter values of the 3D printer. The geometrical overgrowth showed 28.55% at 48 vol% and 36.94% at 58 vol%. As the volume fraction of zirconia increased, the geometrical overgrowth increased and the cure depth reduced.