A COMPARISON OF 3 WETTING AGENTS USED TO FACILITATE THE POURING OF DIES

This study compared the effect of a clinical surfactant and one of thr ee laboratory surfactants used before pouring dies from elastomeric im pression materials. A total of 154 impressions were recorded. Hydrosys tem surfactant was used before the recording of 78 of these impression s. A total of 154 dies were poured with Wax-mate, Tensilab, or Hydrosy stem surfactants and examined for surface voids by an examiner who was unaware which wetting agent was used Six dies were grossly defective and discarded When the Hydrosystem surfactant had not been used during impression recording there was no significant difference between Hydr osystem (mean 10.2 +/- 8.8 voids, n 25), Wax-mate (mean 13.1 +/- 14.4 voids, n 25), and Tensilab (mean 14.9 +/- 11.6 voids, n 21) surfactant s when the dies were poured. When Hydrosystem surfactant was used duri ng impression recording, there was no significant difference between t he number of voids on dies produced with Hydrosystem (mean 3.8 +/- 3.9 voids, n 26), Wax-mate (3.9 +/- 3.3 voids, n 25), or Tensilab (3.7 +/ - 4.9 voids, n 26) surfactants. However, each of the groups in which H ydrosystem surfactant was used before impression recording resulted in dies with significantly fewer voids than when it had not been used, i ndependent of the surface wetting agent used in the pouring of dies (p < 0.05). To reduce the number of voids in laboratory dies, this in vi tro study suggested that a topical surfactant should be used before an impression is recorded.