Ease of Use and Extrusion Forces of Automix Impression Materials

Objectives: Extrusion Forces of a newly developed experimental super-quick setting Polyether Medium Body Impression material in 50 ml cartridge delivery were compared with a conventional Polyether material and VPS materials of medium consistency. Extrusion forces influence ease of use of automix impression materials and may affect individual extrusion speed during application.
Methods: For this study an experimental super-quick setting Polyether Medium Body material (3M, # VT-PENG-ABF-G-0011, EXP) was compared to Polyether Medium Body material Impregum Soft Quick Step (3M, #4545292, IMP) and four VPS impression materials with medium consistency: Aquasil Ultra+ Medium Fast Set (Dentsply, #160926, AUM), Aquasil Ultra+ Heavy Fast Set (Dentsply, #171201, AUH), Flexitime Monophase (Kulzer, #K010103, FXM) and Imprint II Monophase (3M, #N946635, IMT). For each material consistencies were determined according to ISO4823 (n=5) and extrusion forces from the dual-cartridges were determined (n=5) using the recommended static mixing tips with a ZWICK testing machine Z020 (load cell 5 kN) at two different extrusion speeds (150mm/min and 75mm/min). Room conditions were 23°C and 50% rel. humidity.
Results: Mean values and standard deviations of consistency and extrusion force measurements are shown in the table below. Data were analyzed by one-way-Anova and Tukey Test (p<0.05). Within each column means that do not share a letter are significantly different. No strict correlation between consistencies and extrusion forces could be found.
Conclusions: EXP shows extrusion forces which lie within the broad range that is spanned by VPS materials. In comparison to the other Polyether (IMP) EXP shows significantly lower extrusion forces leading to easier and more convenient application.