Effect of surface finishing treatments on the color stability of CAD/CAM materials

Abstract

The aim of this study was to evaluate the effect of different surface finishing processes on the color stabilities of lithium disilicate glass-ceramics, zirconia-reinforced lithium silicate ceramics, and resin nanoceramics after artificial ageing. MATERIALS AND METHODS. 216 samples were prepared from 3 different CAD/CAM materials (LAVA Ultimate, IPS e.max CAD, VITA Suprinity) with A1 HT color at a size of 14 × 12 mm and a thickness of 0.5 ± 0.05 mm. Color measurements of the samples were performed with a spectrophotometer using color parameters and CIE Lab color system on a gray backing between baseline color and after 5000 cycles of artificial ageing in 4 stages (i.e. the first measurement before the treatment, the second measurement after polishing, the third measurement after cement application, and the fourth measurement after artificial ageing). The results were evaluated using the Variance analysis and Fisher's LSD test. RESULTS. Resin nanoceramics (LU) exhibited higher color change values than zirconia-reinforced lithium silicate (VS) and lithium disilicate (EC) ceramics after artificial ageing. Manual polishing and glazing resulted in similar color change for LU and VS (P>.05). In the EC group, glazing provided statistically different results as compared to the manual polishing and control groups (P<.05). Among the ceramic groups, color change values of the subgroup, which was treated by glazing, of the zirconia-reinforced lithium silicate (VS) and lithium disilicate (EC) samples were below the clinically acceptable level (ΔE < 3.5). CONCLUSION. The lowest color change for all stages was observed in Vita Suprinity.

Influence different polishing systems on roughness and colour stability of chairside CAD/CAM blocks with laminate veneer thickness

“…10,13 Many authors have suggested that Lava Ultimate has the highest colour change compared to other ceramics after various surface treatments. 17,29 Similar results were found in this study as well.…”

Translucency, color stability, and biaxial flexural strength of advanced lithium disilicate ceramic after coffee thermocycling

“…In addition, glazing was reported to lead to higher color stability and better mechanical properties. 27,29 However, different surface treatments may lead to different results. 25 Considering the novelty of ALDS, future studies investigating optical and mechanical properties of this material after different processes such as brushing, thermomechanical aging, and cyclic loading are needed to comprehensively understand its limitations.…”

“…A digital spectrophotometer (CM‐26d; Konica Minolta) 15 was used for color coordinate ( L *, which corresponds to lightness; a *, which corresponds to redness; b *, which corresponds to yellowness) 13,29,32 measurements. This spectrophotometer has a diffused illumination integrating sphere system (8° viewing) and two specular component modes (specular component included and excluded).…”

“…Esthetic outcomes of a ceramic restoration depend on its translucency and optical properties 25,26 . In addition, color stability is an important parameter for a long‐lasting restoration 27 as color change may affect the quality of a restoration 28,29 . However, along with optical properties, success of a restoration also depends on material's mechanical properties 30 .…”

Effect of thickness, cement shade, and coffee thermocycling on the optical properties of zirconia reinforced lithium silicate ceramic

“… 4 Again, no cementation was performed, which may be the reason for differences from the present study results in terms of perceptibility. Ozen et al 29 studied the color stability of CAD‐CAM materials after cementation with a translucent shade resin cement and thermocycling. The effect of translucent cement applied on the color of 0.5 mm ZLS specimens was similar to the effect of the cements recorded after cementation in the present study.…”