Surface characterization and optical properties of zirconia-reinforced lithium silicate ceramics against different mouthwashes and thermocycling

Abstract

Aim: To evaluate color stability (ΔE₀₀), translucency (TP), and surface roughness (Ra) of zirconia-reinforced lithium silicate (ZLS) with lithium disilicate (LS) against different mouth rinses after thermocycling.

Methods: A total of 270 specimens were prepared: LS (IPS Emax CAD (group EC)), ZLS-1 (Vita Suprinity (group VS)), and ZLS-2 (Celtra Duo (group CD)). For each specimen, ΔE₀₀, TP, and Ra measurements were recorded with a clinical spectrophotometer (CM-3600A) and a 3D non-contact profilometer (AEP Nanomap-1000WLI), respectively, between baseline and after 10000 cycles of thermal cycling. Each group was divided into six subgroups (n=15) according to the immersion solution: five mouthwashes (Meridol, Klorhex, Listerine Cool Mint, Listerine Healthy White Natural Lemon&Salt, and Curasept ADS 212), and distilled water for 72 hours. Statistical analysis was performed by using a three-way robust ANOVA with Tukey HSD test (α=0.05).

Results: Listerine Lemon&Salt and Cool Mint caused the highest ΔE₀₀ and Ra values, while TP values of tested mouthwashes were similar (p=0.051). Group EC had the highest ΔE₀₀ and Ra values with the lowest TP values against mouthwashes (p<0.05).

Conclusion: Prolonged use of mouthwashes may cause color change and increased surface roughness in LS more than ZLS. Patients should be advised to use alcohol-containing mouthwashes with caution in daily use.