Three new silicone-based impression materials manufactured for use in dentistry (Silasoft, CutterSil and Xantopren) have been evaluated for the silicone mold sweat test in humans and mice and compared with the well-known silicone material Elasticon. The new materials produced more translucent molds and the sweat impressions show less contrast than Elasticon. Molds made of Xantopren and CutterSil retained air bubbles that make counting of sweat impressions more difficult than with Elasticon. The density of sweat droplets from human skin varied depending on the silicone used, but differences were not significant. In the mouse hindpaw, total counts of sweat droplets were similar in Elasticon, Silasoft and CutterSil molds but slightly higher in Xantopren molds. There was good correlation between the number of sweat droplet impressions recorded with Elasticon and that recorded with the new materials, with the exception of CutterSil, both in humans and mice. From these results we recommend Silasoft as a valid substitute of Elasticon for the evaluation of sudomotor function with the silicone impression technique.