Color match of ultra‐translucency multilayer zirconia restorations with different designs and backgrounds

Abstract

AbstractPurposeThe purpose of this in vitro study was to assess the color match of ultra‐translucency multilayer zirconia restorations with different designs and backgrounds.Materials and methodsThirty ultra‐translucency multilayer zirconia crown specimens were made in VITA classical shade B2 for a prepared maxillary central incisor. The specimens were divided into three groups based on the restoration design: veneered zirconia with a trestle design (VZT), veneered zirconia with a dentin core design (VZD), and full‐contour zirconia (FCZ). In the groups VZT and VZD, the zirconia specimens were layered with a feldspathic veneering ceramic. The specimens were seated on five different backgrounds: shade B2 composite resin, shade B2 zirconia, copper‐colored metal alloy, silver‐colored metal alloy, and the prepared central incisor. CIELab values of the labial middle sections of the crown specimens were measured with a spectrophotometer. Color differences between the specimens and a shade B2 VITA classical tab (as a control) were calculated from the ΔE*ab formula and compared with an acceptability threshold (ΔE*ab = 3.7) to be clinically explicated.ResultsMean ΔE*ab values ranged between 1.17 and 8.48. The restoration design, the background type, and their interaction affected the ΔE*ab (p < 0.001). The mean ΔE*ab values for VZT with all backgrounds and for VZD with the silver‐colored metal background were greater than the threshold (p < 0.001), whereas the mean ΔE*ab values for VZD with the other backgrounds and FCZ with all backgrounds were less than the threshold (p = 1).ConclusionsRestoration design and background type affected the color match of ultra‐translucency multilayer zirconia restorations. VZT restorations on all backgrounds and VZD restorations on a silver‐colored metal background showed color mismatches. However, VZD restorations on the other backgrounds and FCZ restorations on all backgrounds demonstrated color matches.