Hydrophilicity of Precision Impression Materials During Working Time

Objective: Very limited information is available about the hydrophilicity of impression materials in the unset stage when most clinical relevant and used for syringing. Goal of the present study was to investigate the hydrophilicity of unset light bodied precision impression materials available from the hand dispenser. Method: Seven fast set light bodied precision impression materials, Impregum Soft Quick Step Light Body (3M ESPE, a new fast setting material, ImSQ), Honigum Automix Light Fast (DMG, HoAF), Exafast NDS Injection (GC, ExNDS), Take 1 Fast Stet Wash (Kerr, Tak1F), Aquasil Ultra LV Fast Set (Dentsply, AqULV), Aquasil Ultra XLV Fast Set (Dentsply, AqUXLV), Affinis light body fast (Coltène, Aflf), and one regular setting material, Impregum Garant Soft Light Body (3M ESPE, ImS), were compared. Contact angles were measured at room temperature within the recommended working time of the manufacturer. 45 seconds after mix a water drop was placed on the material. The contact angle of the drop was measured immediately (Test 1) and 10 seconds later (Test 2). Data were determined with a Drop Shape Analysis System DSA10 (Krüss GmbH, Hamburg) employing a video analysis. Results: The following contact angles Test 1/Test 2 (units in °, SD in brackets) were determined (n = 5): ImSQ: 66,7/32,3 (1,1/0,9), HoAF: 101,2/65,5 (1,0/1,4), ExNDS: 105,3/58,0 (1,8/1,5), Tak1F: 120,4/67,5 (6,5/7,7), AqULV: 108,6/64,9 (2,2/2,6), AqUXLV: 109,0/44,9 (4,0/2,1), Aflf: 101,4/53,8 (0,4/2,6), ImS: 66,2/30,7 (1,5/1,1). Results were analyzed by ONE-WAY ANOVA and Tukey Test (p<0,01). The contact angles of the materials ImSQ and ImS were found to be significantly lower than those of the materials HoAF, ExNDS, Tak1F, AqULV, AqUXLV, Aflf. Conclusion: Materials ImSQ and ImS are significantely more hydrophilic in the unset stage than HoAF, ExNDS, Tak1F, AqULV, AqUXLV, Aflf.