The impact of zirconium dioxide nanoparticles on the color stability of artificially aged heat-polymerized maxillofacial silicone elastomer.

The limited service life of craniofacial prostheses due to degradation and color instability is a significant challenge. This study aimed to determine how zirconium dioxide (ZrO) nanoparticles affect the color stability of M511 heat temperature vulcanizing (HTV) maxillofacial silicone elastomers after artificial aging. ZrO nanoparticles were added at concentrations of 1, 2, and 3 wt% to M511 HTV silicone elastomer. Two intrinsic silicone pigments were used (red and mocha). Silicone with pigment and without ZrO nanoparticles were used as the control. Eighty disk-shaped specimens were fabricated and divided into eight experimental groups, each containing ten specimens (n = 10). All specimens were subjected to artificial aging, and color changes were recorded at 252, 504, and 1008 h intervals. The La b * values were measured using a colorimeter and the CIE-Lab system. To interpret the recorded color differences, a 50:50 percent perceptibility threshold (ΔE = 1.1) and acceptability threshold (ΔE = 3.0) were implemented. A one-way analysis of variance and Tukey's post hoc test at a significance level of 0.05 were used for the statistical analysis. We found that every evaluated specimen group exhibited a chromatic change (ΔE* > 0). The ΔE* values for the mocha pigments with and without ZrO nanoparticles were below the perceptible threshold (1.1 units). The ΔE* values of the red pigment with and without ZrO nanoparticles were significantly higher than the acceptable threshold (P < 0.000). According to the findings of this study, all the specimens underwent color changes (ΔE* > 0). The red pigment exhibited highly significant chromatic alterations. In contrast, mocha pigments with and without ZrO nanoparticles exhibited the least color change and were below the perceptible threshold. ZrO nanoparticles provided important protection and showed a reduction in color change.