الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 123 |  |  |
| | | from | 123 | | |
Abstract
Four of new ceramic materials indicate for thin laminate veneers were used in this study, Enamic from Vita which combines the properties of ceramic and polymer, it belongs to a new substance class, known as ”hybrid-ceramic”. It consist of a hybrid structure with two interpenetrating networks of ceramic and polymer, a so-called double network hybrid (DNH). And Suprinity also from Vita which is a glass ceramic enriched with zirconia (10% by weight) reinforced lithium silicate, in order to obtain the world’s first zirconia reinforced lithium silicate ceramic (ZLS), a tough hybrid ceramic Cerasmart nanohybrid ceramic block has best characteristics of a high strength ceramic and a composite with a revolutionary of flexible nano ceramic matrix structure, and Ultra translucent zirconia (Anterior BruxZir).
The purpose of the present study was to evaluate the effect of different thicknesses of different ceramics on color reproduction, translucency and the effect of cementation.
As the result, eighty rectangular shaped specimens having final shade of A2 high translucency were obtained as a total number of the specimens from the four different materials divided into four groups as follows:
group A: Vita Enamic (n=20)
group B: Cerasmart (n=20)
group C: Vita Suprinity (n=20)
group D: Anterior Bruxzir (n=20)
Each ceramic group will be further subdivided into two subgroups according to thickness of ceramic block as show in table (8). Dark (A3.5) and light (A1) substrates were fabricated from composite resin material and ceramic specimens cemented on it for color and translucency testing.
All specimens then were cleaned in an ultrasonic cleaner for 3 minutes. Surface treatment of the unpolished inner surface of the ceramic specimens was done according to manufacturer’s instructions. For group A (Vita Enamic) and B (Cerasmart) the unpolished surface was etched with (Vita ceramic etch) for 60 seconds and for group C (Vita Suprinity) for 20 seconds according to manufacture instructions. As for group D (Bruxzir anterior), Sandblasting was done.
All specimens after different surface treatments were cemented to composite resin substrate by translucent adhesive resin cement, and then all ceramic specimens were evaluated after cementation. ∆E of color reproduction of shade A2 of Vita classical shade guide were measured by Pre-adjusted ∆E of Easy shade compact Color difference from A2 shade,
A quantitative measurement of relative translucency was obtained by measuring the CIELAB coordinates of the specimens after backing with a white background and then black background using the Vita easy shade compact for each specimen three measurements were taken and their average was recorded.