title: The physical properties of packable and conventional posterior resin-based composites: a comparison.
abstract: BACKGROUND
  The authors compared the physical properties of three packable hybrid resin-based composites with those of a conventional hybrid and a microfill composite material advocated for use as posterior restorative materials. They evaluated diametral tensile strength, or DTS; compressive strength, or CS; flexural strength, or FS; and depth of cure, or DC.
  
  
  METHODS
  The authors studied the following resin-based restorative materials: three packable composites, Alert Condensable Composite (Jeneric Pentron), SureFil High Density Posterior Restorative (Dentsply Caulk) and Solitaire (Heraeus Kulzer); one conventional hybrid composite, TPH Spectrum (Dentsply Caulk); and one microfill, Heliomolar Radiopaque (Ivoclar-Vivadent). The authors evaluated DTS, CS, FS and DC, according to American National Standards Institute criteria. They made scanning electron micrographs of the packable resin-based composites.
  
  
  RESULTS
  Results demonstrated that the conventional hybrid, TPH Spectrum, had significantly greater DTS and FS than other resin-based composites. Alert and SureFil had comparable DTS and FS, which were significantly greater than Heliomolar's DTS and FS. Solitaire had significantly lower DTS and FS than all other resin-based composites. SureFil had the highest CS, followed by TPH Spectrum, Solitaire and Alert, which were comparable and had significantly greater CS than Heliomolar. TPH Spectrum and Alert had significantly greater DC than all other resin-based composites, followed in decreasing order by SureFil, Solitaire and Heliomolar.
  
  
  CONCLUSIONS
  While the packable composites tested in this study had physical properties superior to those of the microfill composite, they were no better suited for use as a posterior restorative material than was the conventional hybrid resin-based composite.
  
  
  CONCLUSIONS
  Packable composites may be easier for clinicians to handle than conventional resin-based composites; however, their physical properties were not superior to those of the conventional small-particle hybrid resin-based composite. In addition, these materials may have the clinical drawback of increased wear and surface roughness that was seen with early, large-particle composite restorative materials.
authors: University of Iowa, College of Dentistry, Department of Operative Dentistry, Iowa City 52242, USA. deborah-cobb@uiowa.edu
authors: D S
authors: DS
authors: Cobb
authors: K M
authors: KM
authors: MacGregor
authors: M A
authors: MA
authors: Vargas
authors: G E
authors: GE
authors: Denehy
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003188:Composite Resins / Q000737:chemistry*; D019245:Compressive Strength; D003793:Dental Restoration, Permanent; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008963:Molar; D010316:Particle Size; D018583:Pliability; D011140:Polyurethanes / Q000737:chemistry; D013718:Tensile Strength
chemical_list: D000180:Acrylic Resins; C406265:Alert composite resin; C029012:Composite Dental Resin; D003188:Composite Resins; C513708:Heliomolar; D011140:Polyurethanes; C113049:Solitaire composite resin; C403464:SureFil packable composite; C113300:TPH hybrid; C513703:Vivadent