Experimental hydrophilic vinyl polysiloxane (VPS) impression materials incorporating a novel surfactant compared with commercial VPS

ObjectivesTo formulate experimental hydrophilic (Exp) VPS impression materials incorporating a novel surfactant (Rhodasurf CET-2), and to compare their contact angles (CAs) with commercial materials, before/after disinfection.MethodsCAs were measured immediately after setting and after disinfection (1% NaOCl; 30 min and 24 h), together with their change whilst a droplet remained on the materials surface (over 10, 20, 30 60 and 120 s), on three commercial (Aquasil Ultra-Monophase [Aq M], Elite HD-Monophase [Elt M], Extrude Medium-bodied [Extr M]) and four experimental (Exp I-IV) materials, using the Drop Shape Analysis 100 technique. The results were compared statistically.ResultsCAs of all experimental materials were within the range of those obtained for the commercial materials, with the exception of Exp-IV, which presented with the lowest CAs at the three time points. The control Exp-I was hydrophobic at all three time points (CAs ∼100+), as was Elite. Immediately after setting, Aq M had low CAs but these increased significantly after 30 min of disinfection. After twenty four hours' disinfection CAs of all Exp/commercial VPS increased significantly compared to immediately after setting. The CAs of droplets left on the material (120 s) decreased with time, even after disinfection, except for Exp-I.SignificanceThe novel surfactant Rhodasurf CET-2 in Exp-III and IV, is an effective surfactant, retaining a low CA after disinfection, compared with Igepal CO-530 in Aq M. Disinfecting VPS impression materials for more than 30 min increases their surface CAs, and therefore prolonged disinfection periods should be avoided.