Effect of surfactant’s molecular weight on the wettability of vinyl polysiloxane impression materials after immersion disinfection

The aim of this study was to develop novel hydrophilic vinyl polysiloxane (VPS) materials incorporating novel hydrophilic agents (Rhodasurf CET-2 and CET-5). In addition, experimental material’s wetting properties (contact angles) were compared with commercial materials upon immersion in various media. Three commercial (Aquasil Ultra-Monophase [Aq M], Elite HD-Monophase [Elt M], Extrude Medium-bodied [Extr M]) and five experimental (Exp I-V) materials were used in this study. The contact angles were measured at time intervals (10, 30, 60 and 120 s), immediately after setting and after immersion using a Drop Shape Analysis (DSA). The results were analyzed statistically using the SPSS software. The largest contact angle (at 10 s) was recorded for Elt M (108.78±6.04) that was significantly larger (p < 0.05) than Aq M (36.19±4.05) and Extr M (44.65±3.11). The contact angles for experimental materials Exp-I (108.35±4.45), Exp-II (104.08±4.70) closely matched to Elt M (108.78±6.04) however were significantly larger (p < 0.05) than other experimental groups Exp-III (68.50±4.29), Exp-IV (35.26±3.46), Exp-V (24.47±5.92) and commercial materials Aq M (36.19±4.05) and Extr M (44.65±3.11). In conclusion, the experimental vinyl polysiloxane materials containing the surfactant (Rhodasurf CET-2) showed lower contact angles compared to controls (Exp-I and Exp-II) and commercial vinyl polysiloxane impression materials. The decrease in contact angles was dependent on the concentration of surfactant (Rhodasurf CET-2) in the materials. In addition, the smaller molecular weight surfactant (Rhodasurf CET-2) resulted in lower contact angles compared to the larger molecular weight surfactant (Rhodasurf CET-5).