Evaluation of Color Change and Hardness of Different Maxillofacial Silicone Elastomers after Natural Daylight Aging

Abstract

Facial prostheses used in aesthetic rehabilitation of facial defects contribute to socialization of patients and increase quality of life. Nowadays, maxillofacial silicone is the most widely used material for facial prosthesis. Maxillofacial silicone can be naturally colored to match with the skin but time-dependent discoloration occurs. Among various factors that cause discoloration, the importance of solar radiation has been revealed. The aim of this study was to evaluate color change and hardness of silicones with different physical properties. Three maxillofacial silicones (M511, Derma-sil 10, and Derma-sil 30) with different physical properties were used in the study. Disc-shaped specimens (n=10) were prepared in 15 mm in diameter and 2 mm in thickness from orange-brown and red colors. Then the specimens exposed to natural daylight. Color coordinates (L*, a*, b*) were determined using spectrophotometer and Shore A hardness values detected using hardness device before and after aging. The color change (ΔE) and hardness of the specimens were calculated and statistically analyzed (α=0.05). Color change of red specimens were significantly higher in M511 group and color change of orange-brown specimens were significantly higher in Derma-sil 30 group. Also aging significantly decreased the hardness values of M511 red and orange-brown groups than other groups. The color and hardness of the maxillofacial silicones are affected by daylight. It was observed that the color changes of 3 different maxillofacial silicones were in acceptable limits (ΔE<3) at the end of aging period.

Keywords

• Maxillofacial silicone
• color change
• hardness
• aging

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