Effect of Chemical Disinfectants on the Color Stability of Maxillofacial Silicones: An In Vitro Study.

PURPOSE: To evaluate the effect of chemical disinfection on the color stability of room temperature vulcanizing (RTV) maxillofacial silicone elastomer with and without pigment addition.

MATERIALS AND METHODS: Sixty specimens were obtained from a RTV maxillofacial silicone. The specimens were randomly divided into 6 groups according to pigments and disinfectant to be used (n = 10). NP-DW-nonpigmented silicone specimens to be immersed in distilled water (control). NP-S- nonpigmented silicone specimens to be rubbed with an anti-bacterial soap. NP-CHX-nonpigmented silicone specimens to be immersed in chlorhexidine gluconate solution (2%). P-DW-pigmented silicone specimens to be immersed in distilled water (control). P-S-pigmented silicone specimens to be rubbed with antibacterial soap. P-CHX-pigmented silicone specimens to be immersed in chlorhexidine gluconate solution (2%). Disinfection was conducted 6 times a day for 60 days simulating 1 year of usage. Color was evaluated after 60 days (disinfection period) using a reflectance spectrophotometer. Color alterations were calculated by the CIE L∗ a∗ b∗ system. Data were analyzed by t-test, one-way ANOVA, and Tukey test (α = 0.05).

RESULTS: NP-S and P-S exhibited the highest color alterations, whereas NP-DW and P-DW the lowest color alterations.

CONCLUSION: Disinfection procedures affect the color stability of maxillofacial silicone. Chlorhexidine gluconate solution (2%) can be effectively used as a chemical disinfectant for maxillofacial prostheses. Antibacterial soap produced clinically unacceptable color changes in the silicone, hence is not advisable as a disinfectant.