Effect of skin disinfectants on the color stability of maxillofacial silicone elastomers: an in-vitro study

Although daily chemical disinfection is crucial for preventing biofilm formation on maxillofacial silicone prostheses, it frequently induces material degradation and color instability. Therefore, this study aimed to evaluate the effects of various skin and mucosal disinfectants on the color stability of three maxillofacial silicone elastomers. 180 disk-shaped specimens were fabricated from three addition-cured platinum silicones: M511, TechSil S-25, and Z004. The specimens were pigmented to simulate a skin color and randomly divided into six groups based on the disinfectant used: distilled water (control), hypochlorous acid, 67.2% ethyl alcohol, micellar water (cationic surfactant), and two multi-purpose contact lens solutions (containing alexidine dihydrochloride and polyquaternium-1). A 12-month clinical use simulation was conducted over 2 months, with specimens spray-disinfected 6 times daily. Color coordinates were measured before and after disinfection using a digital spectrophotometer, and color change values were calculated using the CIEDE2000 formula. Data were analyzed using two-way ANOVA and Tukey HSD tests (α = 0.05). There was no significant interaction between silicone type and disinfectant type factors. However, the main effects of both factors were significant ( P < 0.05). Z004 demonstrated significantly higher color stability than M511 and Techsil S-25. Among the disinfectants, hypochlorous acid produced the most remarkable mean color change, whereas the multi-purpose contact lens solutions produced the least. Notably, all recorded values remained below the clinically perceptible threshold (0.7). Multi-purpose contact lens solutions and micellar water may be promising candidates for future investigation as cleaning agents for maxillofacial prostheses, given their minimal impact on color. Also, all recorded values were below the visual perceptibility threshold (ΔE 00 = 0.7) over a simulated 12-month period.