title: Dynamic thermo-mechanical properties of various flowable resin composites.
abstract: BACKGROUND
  This study compared the storage modulus (E'), the loss modulus (E'') and the loss tangent (tan δ) of various flowable resin composites.
  
  
  METHODS
  Grandio Flow (GRF), GrandioSo Heavy Flow (GHF), Filtek Supreme XTE (XTE) and Filtek Bulk Fill (BUL) flowable resins and Clinpro Sealant (CLI) ultra-flowable pit and fissure sealant resin were used. 25 samples were tested using a dynamical mechanical thermal analysis system in bending mode. Measurements were taken within a temperature range of 10 to 55°C. The results were statistically analyzed using mixed-effect and repeated-measure analysis of variance followed by paired multiple comparisons.
  
  
  RESULTS
  For all the materials, the E' values decrease with temperature, whereas the tan δ values increase. Irrespective of the temperature, GHF and GRF present E' and E'' values significantly higher than all the other materials and CLI presents values significantly lower than all the other materials. Observation of the values for all the materials reveals a linear progression of the tan δ values with temperature.
  
  
  CONCLUSIONS
  A variation in temperature within a physiological range generates modifications in mechanical properties without damaging the material, however. Filler content in volume terms appears to be the crucial parameter in the mechanical behavior of tested materials.Key words:Dynamic mechanical thermal analysis, elastic modulus, filler content, flowable resin composites, loss modulus, loss tangent.
authors.affiliation: DDS, research fellow, Département d'Odontologie Pédiatrique, Faculté d'Odontologie, 54000 Nancy, France.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Jager
authors.affiliation: DDS, PhD, Département d'Odontologie Conservatrice, Faculté d'Odontologie, 54000 Nancy, France.
authors.forename: Rémy
authors.initials: R
authors.lastname: Balthazard
authors.affiliation: DDS, research fellow, Département d'Odontologie Conservatrice, Faculté d'Odontologie, 54000 Nancy, France.
authors.forename: Marin
authors.initials: M
authors.lastname: Vincent
authors.affiliation: Professor, Institut Jean Lamour UMR 7198 CNRS, Université de Lorraine, Parc de Saurupt, 54011 Nancy Cedex, France.
authors.forename: Abdessellam
authors.initials: A
authors.lastname: Dahoun
authors.affiliation: DDS, PhD, Institut Jean Lamour UMR 7198 CNRS, Université de Lorraine, Parc de Saurupt, 54011 Nancy Cedex, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Mortier