Effect of chemical aging on color stability and surface properties of stained all-ceramic restorations

Objectives To study the effect of artificial aging on color stability, translucency, and surface roughness of stained all-ceramic restorations. Materials and methods Disc-shaped specimens were fabricated from six different all-ceramic materials: two glass ceramics (Vita Mark II and Empress CAD), two lithium disilicate based ceramics (e.max and Suprinity), and two zirconia-based materials (ZirCAD LT and ZirCAD MT Multi). The discs were stained using two universal stains; (IPS) Ivocolor stain or Vita Akzent stain. Color change (Delta E) and the translucency parameter (TP) were measured before and after artificial aging. The surface roughness (Ra) was evaluated using atomic force microscopy, while the surface microstructure was evaluated using scanning electron microscopy (SEM). Quantitative elemental analysis was performed using the energy dispersive X-ray (EDX). Leached ions were analyzed by inductively coupled plasma (ICP) (n = 12, alpha = 0.05). Results Artificial aging had significantly changed the color (Delta E) and decreased the translucency (TP) of all stained ceramics. The mean surface roughness (Ra) was significantly increased in all specimens, which was also confirmed in the SEM scans. EDX analysis revealed a decrease in the elemental composition of the stained surface as a result of ceramic degradation, except for Ca and Zn in (IPS) Ivocolor stain. Furthermore, the ICP analysis revealed that most compositional elements of stain and glaze were detected in the aging solution. Conclusions Chemical aging had significantly affected the optical parameters and surface texture of stained monolithic ceramics. Clinical Significance Stained ceramics are liable to color degradation. Each type of stain should be used with its corresponding type of ceramic. Stained all-ceramic restorations are liable to color change and surface degradation during function.

Automated summary

Artificial aging significantly impacts the color stability, translucency, and surface roughness of stained all-ceramic restorations. Chemical aging affects the optical parameters and surface texture of stained monolithic ceramics. Stained ceramics are susceptible to color degradation and surface changes during function.