Comparison of light transmittance in different thicknesses of zirconia under various light curing units.
OBJECTIVE
The objective of this study was to compare the light transmittance of zirconia in different thicknesses using various light curing units.


METHODS
A total of 21 disc-shaped zirconia specimens (5 mm in diameter) in different thicknesses (0.3, 0.5 and 0.8 mm) were prepared. The light transmittance of the specimens under three different light-curing units (quartz tungsten halogen, light-emitting diodes and plasma arc) was compared by using a hand-held radiometer. Statistical significance was determined using two-way ANOVA (α=.05).


RESULTS
ANOVA revealed that thickness of zirconia and light curing unit had significant effects on light transmittance (P<.001).


CONCLUSIONS
Greater thickness of zirconia results in lower light transmittance. Light-emitting diodes light-curing units might be considered as effective as Plasma arc light-curing units or more effective than Quartz-tungsten-halogen light-curing units for polymerization of the resin-based materials.
Department of Prosthodontics, Faculty of Dentistry, Gazi University, Ankara, Turkey.
Isil
I
Cekic-Nagas
Ferhan
F
Egilmez
Gulfem
G
Ergun