A tissue culture cytotoxicity study was conducted to evaluate the biocompatibility of polydimethylsiloxane (PDMS) fluid with human cells. Dimethylsiloxane, hydroxy-functional silica filled gum served as the negative control; while latex catheter served as the positive control. Each test material was used to saturate a sterile 1.3 cm filter pad, which was placed in direct contact with a confluent monolayer of human embryonic foreskin cells and incubated for 24 hours. After incubation, the cultures were examined microscopically at 10x magnification and compared to positive and negative controls to evaluate cytotoxicity. The results of these examinations were reported as no cytopathic effect or as a cytopathic effect, rated as 1, 2, or 3. A rating of 1 denoted a slight reaction; 2 represented a distinct reaction in areas around the sample with no cell death evident; 3 represented a severe reaction with cells dead and areas of the cell sheet lifted. No cytopathic effect was reported for the polydimethylsiloxane fluid.