title: Effect of filler size and temperature on packing stress and viscosity of resin-composites.
abstract: The objective of this study was to investigate the effect of filler size on the packing stress and viscosity of uncured resin-composite at 23 °C and 37 °C. A precision instrument used was designed upon the penetrometer principle. Eight resin-composite materials were tested. Packing-stress ranged from 2.60 to 0.43 MPa and viscosity ranged from 2.88 to 0.02 MPa.s at 23 °C. Values for both properties were reduced significantly at 37 °C. Statistical analysis, by ANOVA and post hoc methods, were carried out to check any significant differences between materials tested (P < 0.05).
  
  
  CONCLUSIONS
  Filler size and distribution will affect the viscosity and packing of resin-composites during cavity placement.
authors.affiliation: School of Dentistry, University of Manchester, Higher Cambridge Street, Manchester M15 6FH, UK; E-Mails:  julian.satterthwaite@manchester.ac.uk  (J.S.);  nick.silikas@manchester.ac.uk  (N.S.).
authors.forename: Haitham
authors.initials: H
authors.lastname: Elbishari
authors.forename: Julian
authors.initials: J
authors.lastname: Satterthwaite
authors.forename: Nick
authors.initials: N
authors.lastname: Silikas
mesh_terms: D003188:Composite Resins / Q000737:chemistry*; D008422:Materials Testing; D013314:Stress, Mechanical; D013696:Temperature; D013997:Time Factors; D014783:Viscosity
chemical_list: D003188:Composite Resins