Effects of Thixotropic Agent on the Fluidity of Silicone Materials

Abstract

In the intrinsic coloring technique of facial prostheses, it is necessary to laminate an appropriate quantity of silicone materials on the appropriate place. A thixotropic agent （TA） was applied to silicone materials to improve their high fluidity. The aim of this study was to evaluate the effects of the amount of TA on the fluidity of a maxillofacial silicone （A-2186） and two silicone materials （KRS-10-2, KRS-C2-2）. Specimens for A-2186 and KRS-10-2 were prepared with different amounts of the corresponding TA: from 0 to 3 drops for 10 g of base silicone. 0.1 g of mixed silicone was placed on a glass plate and then the plate was positioned horizontally or vertically. The horizontal diameter and the vertical length of each specimen were measured until 15 minutes after the start of mixing. A load of 14.7 N was applied to the glass plate over 0.5 ml mixed silicone for the consistency test, and the diameter of silicone after 15 minutes was measured. All silicone materials without TA showed high fluidities, while all silicone materials mixed with more than 0.4 drops showed low or no fluidity. These results suggested that a small amount of thixotropic agent is effective to improve the fluidity.