The Influence Of Different Post-cores On The Color Of Cercon Zirconia Crown

Objective: Cercon Zirconia (Y-TZP, Yttria Tetragonal Zirconia Polycrystal) all-ceramic smart Ceramics system (CAD / CAM) is a gradually emerging kind of all-ceramic restorative systems in prosthodontics in recent years . It is produced by sintering zirconia, which is used to as substrate material, and special zirconia veneering porcelain in a low temperature. The purpose of this research is to find out the effects on the the color of Cercon zirconia all-ceramic with different thickness of zirconia substrate material through experimental research in vitro, and to analyse the color parameters of Cercon Zirconia all-ceramec under the context of different post-core materials by using shade-eye computer-aided colorimeter and explore the law of the effects placed on the all-ceramic color by different post-core materials, and finally provide a theoretical and laboratorial basis to choose a goodlooking and economic material in clinic.Methods: In a dark room, the color parameters of Cercon Zirconia specimens,zirconia all-ceramic crown were measured by shade-eye computer-aided colorimeter on a black bench, and the results were statistically analyzed by SPAA13.0 software.Results: 1,The thickness of Cercon Zirconia all-ceramic substrate material had an impact on the color of the whole all-ceramic crown when it was within the clinically used range. The Lightness value (L *) and saturation value(b *) went up with the increase of the thickness, while the hue value( a * ) changed little.2,The influence of different post-core materials on Cercon Zirconia All-ceramic color: the difference of L*,a * and b *value of Cercon Zirconia All-ceramic specimens under 4 kinds of post-core specimen background had statistical significance(P<0.05).3,The chromatism of Zirconia all-ceramic under post-core background of different materials(â–³E)Theâ–³E between nickel-chromium alloy post-core specimens and gold-plated nickel-chromium alloy post-core specimens, gold-plated nickel-chromium alloy post-core specimens and resin post-core specimens along with gold alloy post-core specimens and resin post-core specimens were among the acceptable clinical range.Conclusion: the thickness of Zirconia ceramic substrate materials had a certain influence on the entire Zirconia all-ceramic color.With the thickness increasing, the brightness of all-ceramic zirconia increased and it tended to be yellow. The color of different post-core materials would affect the Zirconia all-ceramic restoration. The all-ceramic specimens under resin post-core background had the highest L* value and brightness, and those specimens under gold-plated Ni-Gr alloy post-core background had the highest a* value, the it tends to be red, while those specimens under gold alloy post-core background had the highest b* value, and it tended to be blue. So materials with warm color such as resin post-core and gold alloy post core specimens were recommended to be used to conduct Zirconia all-ceramic restoration in clinic.