The Effect of Nano Zinc Oxide Particles on Color Stability of MDX4-4210 Silicone Prostheses

Abstract

Objective This article aimed to study the effect of different concentrations of nano zinc oxide particles on the color change of MDX4–4210 facial silicone elastomer after artificial aging. Materials and Methods Silicone specimens (N = 150) were fabricated by incorporating intrinsic pigments and divided into three groups—white, yellow, and red, each group consisting of 50 specimens (n = 50). In each color, specimens were subdivided into five subgroups according to the quantity of zinc oxide nanoparticles (0, 0.5, 1.0, 1.5, and 2.0% weight), where the 0% weight served as the control in each group. All specimens were then subjected to artificial aging using an accelerated aging machine chamber for 12, 24, 48, and 72 hours. L*a*b* values of specimens were noted after a different aging period by a spectrophotometer and ∆E* was calculated. Statistical Analysis Two-way repeated analysis of variance (ANOVA) was done to examine the effects under test conditions (concentration and aging time) of each color group. Then color, concentration, and the aging period were subjected to three-way repeated ANOVA to investigate the effects of different colors and concentrations on ∆E*. Bonferroni’s test was performed to identify differences between groups. The significant level was at p = 0.05. Results The control group showed significantly higher ∆E* values than the test groups. The 1.5% test group showed significantly lower ∆E* compared with the others. The 0.5 to 2.0% of nano zinc oxide significantly decreased the color change of the silicone elastomer (p < 0.05), but there were no significant differences among groups. Conclusions Incorporation of 1.5% of nano zinc oxide can improve the color stability of silicone prosthesis (MDX4–4210).

An overview of recent progress in dental applications of zinc oxide nanoparticles

“…147 The previous research exhibited that incorporation of ZnO NPs at 2.0 to 2.5% by weight into silicone could improve the mechanical properties, including hardness, tensile and strength. 153 Popović synthesized a new composite material containing PMMA and ZnO NPs to identify its properties and behavior of modied PMMA. The ZnO NPs in the matrix of PMMA led to an increase of density owing to the reduced presence of residual monomers.…”

“…150 Charoenkijkajorn and Sanohkan indicated that addition of 0.5 to 2.0% of ZnO NPs remarkable decreased the color change of the silicone elastomer, and addition of 1.5% of ZnO NPs could improve the color stability of silicone prosthesis. 153 Moreover, Cierech et al investigated the nal ZnO NPs concentration on cytotoxicity and ZnO NPs released from PMMA-ZnO nanocomposites and the ZnO NPs layer produced on pure PMMA before being used as an alternative material for denture bases. 81 Summary of studies examining use of ZnO NPs in prosthodontics applications are shown in Table 6.…”

“…147 The previous research exhibited that incorporation of ZnO NPs at 2.0 to 2.5% by weight into silicone could improve the mechanical properties, including hardness, tensile and strength. 153 …”

“… 150 Charoenkijkajorn and Sanohkan indicated that addition of 0.5 to 2.0% of ZnO NPs remarkable decreased the color change of the silicone elastomer, and addition of 1.5% of ZnO NPs could improve the color stability of silicone prosthesis. 153 …”

Effect of Accelerated Aging on the Sorption and Solubility Percentages of Silicone Facial Prostheses

“…[5][6][7]9 The degradation of the physical and mechanical properties of a silicone prosthesis is related to its exposure to ultraviolet rays, polluted air, and humidity, as well as its inadequate cleaning and daily handling. 2,5,6,9 The literature reports that the replacement of a silicone prosthesis occurs from 3 to 12 months after its manufacture due to its degradation. 2,3,6 Sorption and solubility of a material are clinically important characteristics.…”