Objectives: To compare the relative translucency of 5 CAD/CAM ceramic materials for CEREC system.
Methods: Commercial blocks of 5 core materials (VITA AL, VITA YZ [#LL2], In-Ceram Alumina, In-Ceram Spinell and In-Ceram Zirconia [Vita Zahnfabrik, BadSackingen, Germany]) for CEREC CAD/CAM system were selected for the study. The blocks were perpendicularly cut by a water cooled diamond saw (Isomet, Buehler, Lake Bluff, USA), 20 flat specimens were prepared at 0,5mm of thickness for each material and randomly divided in 4 groups (n=5). Specimen were prepared strictly following manufacturer instructions, 3 groups were veneered in a Vita Vacumat 4000 furnace (Vita Zahnfabrik) in order to obtain specimens with an overall thickness of 1,0, 1,5 and 2,0mm. The specimens were finished on a grinder/polisher device and ultrasonically cleaned. For measurements, a spectrophotometer (OceanOptics PSD1000) equipped with an integrating sphere was used. Contrast Ratios (CR) were calculated as Yb/Yw.
Result: The two-way Analysis of Variance (post-hoc: Tukey test) was applied. Result are summarized in table 1.
Tab. 1
Materials | 0,5 mm | 1,0 mm | 1,5 mm | 2,0 mm | Sign. | ||||||||
Mean | SD | Sign. | Mean | SD | Sign. | Mean | SD | Sign. | Mean | SD | Sign. | ||
Zirconia | 0,99 | 0,01 | d | 1,00 | 0,01 | d | 1,00 | 0,01 | d | 1,00 | 0,01 | b | D |
YZ | 0,71 | 0,02 | c | 0,81 | 0,04 | bc | 0,90 | 0,03 | c | 0,94 | 0,01 | a | C |
AL | 0,69 | 0,02 | c | 0,85 | 0,04 | c | 0,87 | 0,06 | bc | 0,95 | 0,02 | a | C |
Alumina | 0,65 | 0,02 | b | 0,79 | 0,03 | b | 0,85 | 0,02 | b | 0,96 | 0,01 | a | B |
Spinell | 0,44 | 0,02 | a | 0,73 | 0,03 | a | 0,81 | 0,06 | a | 0,93 | 0,02 | a | A |
Sign. | A | B | C | D |
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Conclusion: A wide range of translucency was identified in the materials tested. This variability has to be taken into account for the selection of the materials in different clinical situations also related to the thickness clinically required.