Effect of ultraviolet protective agents on maxillofacial silicone elastomer, part 1: Color stability after artificial aging

A Systematic Review on Maxillofacial Prosthesis with Respect to Their Color Stability

The aim of this systematic review was to identify and analyze the findings of various studies that analyzed the changes in the color stability of maxillofacial prosthetic materials after the addition of various colorants and nanoparticles and assess the change in color after being subjected to either natural or artificial accelerated aging as well as outdoor aging. This systematic review was conducted in accordance with the guidelines of transparent reporting of systematic reviews and meta-analysis (PRISMA Statement). The primary objective of this systematic review was to evaluate the color stability of maxillofacial prosthesis. The secondary objective was to assess the effect of various colorants; pigments; opacifiers; UV absorbers-such as inorganic colorants (dry earth pigments); metal oxides; and organic colorants. The time period of the included studies extended from 2013 to 2023. Electronic database search identified a total of 217 studies. Ten studies were included to meet the research question. All 10 included studies analyzed the effect of various colorants and their exposure to various aging and weathering conditions. It was found that various pigments and nanoparticles had an effect on the color stability. Also weathering and aging conditions had a direct effect on the color stability as well. In terms of disinfection, although there was not much color difference observed, highest change in color stability was observed when rubbing or brushing of the prosthesis was carried out. In conclusion, the color stability of maxillofacial prosthetics is a critical factor that influences both patient satisfaction and the overall cosmetic look. The potential of pigments and nanoparticles to enhance the color stability of silicone-based maxillofacial prosthesis has received much research. By avoiding color fading and discoloration brought on by environmental variables including UV radiation, aging, and chemical exposure, the inclusion of various pigments and nanoparticles has been demonstrated to improve the color stability of silicone maxillofacial prostheses.

Effect of 2-ethylhexyl salicylate incorporation on the color stability of different maxillofacial silicone elastomers after outdoor weathering

STATEMENT OF PROBLEM

Silicone elastomers are considered the most favorable materials for the prosthetic rehabilitation of facial defects. However, color change, because of the ultraviolet (UV) light, limits the life of facial prostheses. The addition of 2-ethylhexyl salicylate as a UV-protective may improve the color stability of different maxillofacial silicone elastomers.

PURPOSE

The purpose of this in vitro study was to evaluate the effect of 2-ethylhexyl salicylate on the color stability of 3 different maxillofacial silicone elastomers after outdoor weathering.

MATERIAL AND METHODS

Three different ratios of UV-protective 2-ethylhexyl salicylate (UV-ES) were incorporated into 3 different types of maxillofacial silicones (M511, TechSil S25, and A-2000) in 1%, 2%, and 5% ratios, and a control group for each silicone was generated. A total of 120 Ø15×2-mm disk-shaped specimens were prepared from 3 different silicone elastomers according to the 4 different UV-ES ratio groups (n=10). The specimens were subjected to outdoor weathering in Ankara, Türkiye, from June 2021 to June 2022. Color differences in the specimens were measured at 3 months and 1 year of weathering. The color change values (ΔE) were statistically analyzed by using repeated measures of 3-way ANOVA. The differences were compared by using the Tukey honest significant difference test (α=.05).

RESULTS

No interaction was found among the factors (silicone type, UV-ES ratio, and aging) (P=.29). The highest ΔE values were found in TechSil S-25 (P<.001), while the results were not significantly different between the M511 and A2000 groups (P=.324) The higher ΔE values were found in the control group when compared with those of the UV-ES added group of each material, while the results were not significantly different among the 1%, 2%, and 5% groups (P>.05).

CONCLUSIONS

Incorporating 2-ethylhexyl salicylate into the tested maxillofacial silicones reduced color change.