title: Correlation of shear and dielectric ion viscosity of dental resins - Influence of composition, temperature and filler content.
abstract: Shear viscosity and ion viscosity of uncured visible light-curing (VLC) resins and resin based composites (RBC) are correlated with respect to the resin composition, temperature and filler content to check where Dielectric Analysis (DEA) investigations of VLC RBC generate similar results as viscosity measurements.
  
  
  
  Mixtures of bisphenol A glycidyl methacrylate (Bis-GMA) and triethylene glycol dimethacrylate (TEGDMA) as well as the pure resins were investigated and compared with two commercial VLC dental resins and RBCs (VOCO, Arabesk Top and Grandio). Shear viscosity data was obtained using a Haake Mars III, Thermo Scientific. Ion viscosity measurements performed by a dielectric cure analyzer (DEA 231/1 Epsilon with Mini IDEX-Sensor, Netzsch-Gerätebau).
  
  
  
  Shear viscosity depends reciprocally on the mobility of molecules, whereas the ion viscosity also depends on the ion concentration as it is affected by both ion concentration and mixture viscosity. Except of pure TEGDMA, shear and ion viscosities depend on the resin composition qualitatively in a similar manner. Furthermore, shear and ion viscosities of the commercial VLC dental resins and composites exhibited the same temperature dependency regardless of filler content. Application of typical rheological models (Kitano and Quemada) revealed that ion viscosity measurements can be described with respect to filler contents of up to 30vol.%.
  
  
  
  Rheological behavior of a VLC RBC can be characterized by DEA under the condition that the ion concentration is kept constant. Both methods address the same physical phenomenon - motion of molecules. The proposed relations allows for calculating the viscosity of any Bis-GMA-TEGDMA mixture on the base of the viscosities of the pure components. This study demonstrated the applicability of DEA investigations of VLC RBCs with respect to quality assurance purposes.
authors.affiliation: University Institute, Centre of Polymer Systems, Tomas Bata University in Zlín, Zlín, Czech Republic; Department of Natural Sciences, Bonn-Rhein-Sieg University of Applied Sciences, Rheinbach, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Steinhaus
authors.affiliation: University Institute, Centre of Polymer Systems, Tomas Bata University in Zlín, Zlín, Czech Republic; Faculty of Technology, Department of Production Engineering, Tomas Bata University in Zlin, Zlín, Czech Republic. Electronic address: hausnerova@ft.utb.cz.
authors.forename: Berenika
authors.initials: B
authors.lastname: Hausnerova
authors.affiliation: University Institute, Centre of Polymer Systems, Tomas Bata University in Zlín, Zlín, Czech Republic; Department of Natural Sciences, Bonn-Rhein-Sieg University of Applied Sciences, Rheinbach, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Haenel
authors.affiliation: Department of Natural Sciences, Bonn-Rhein-Sieg University of Applied Sciences, Rheinbach, Germany.
authors.forename: Daniela
authors.initials: D
authors.lastname: Selig
authors.affiliation: Department of Natural Sciences, Bonn-Rhein-Sieg University of Applied Sciences, Rheinbach, Germany.
authors.forename: Fabian
authors.initials: F
authors.lastname: Duvenbeck
authors.affiliation: Department of Natural Sciences, Bonn-Rhein-Sieg University of Applied Sciences, Rheinbach, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Moeginger
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate; D055117:Curing Lights, Dental; D012117:Resins, Synthetic; D013696:Temperature; D014783:Viscosity
chemical_list: D012117:Resins, Synthetic; D017438:Bisphenol A-Glycidyl Methacrylate
keywords: Dielectric Analysis; Filler content; Ion viscosity; Resin based composite; Rheology; Shear viscosity; Visible light curing resin