title: Shear bond strength of an autopolymerizing core buildup composite bonded to dentin with 9 dentin adhesive systems.
abstract: BACKGROUND
  Clinicians have reported unexpected debonding of autopolymerizing composite core buildups. It has been postulated that dentin adhesive systems that incorporate a combined primer-adhesive may be incompatible with autopolymerizing composites. If so, large numbers of existing restorations may be predestined for early failure.
  
  
  OBJECTIVE
  This in vitro investigation examined the shear bond strength values of an autopolymerizing core buildup composite bonded to dentin with 9 dentin adhesive systems.
  
  
  METHODS
  Cylinders of the core buildup composite (2.38-mm diameter) were bonded to moist dentin according to the manufacturers' instructions. Specimens were stored in 37 degrees C water for 1 week, thermocycled (5 degrees C to 55 degrees C, 30-second intervals, 1000 cycles), and returned to water storage overnight. Specimens then were debonded with a universal testing machine at 1.0 mm/min, with results recorded in megapascals. Data were statistically analyzed with a Kruskal-Wallis test, with pairwise Wilcoxon rank sum (Mann-Whitney) tests used to determine significant (P<.05) differences between groups.
  
  
  RESULTS
  The dentin adhesive systems in order of decreasing median bond strength were Optibond FL > One Step, All-Bond 2, Clearfil SE, Amalgambond Plus > Single Bond, Optibond Solo Plus, Tenure > Scotchbond MP.
  
  
  CONCLUSIONS
  No predictable relationship was found between the general formulation of the dentin adhesive agents and shear bond strength values. Material incompatibilities were judged to be dependent on formulation.
authors.affiliation: School of Dentistry, University of the Pacific, San Francisco, CA 94115, USA. mhagge@sf.uop.edu
authors.forename: M S
authors.initials: MS
authors.lastname: Hagge
authors.forename: J S
authors.initials: JS
authors.lastname: Lindemuth
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D003442:Crowns; D001840:Dental Bonding; D003804:Dentin; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D004344:Drug Incompatibility; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D008964:Molar, Third; D011108:Polymers / Q000737:chemistry; D011176:Post and Core Technique; D019279:Resin Cements / Q000737:chemistry; D018709:Statistics, Nonparametric; D013718:Tensile Strength
chemical_list: C070606:Amalgambond; C103506:Bis-GMA, BPDM, HEMA dental-bonding resin; C438313:Clearfil SE Bond; D003188:Composite Resins; D017220:Dentin-Bonding Agents; D008689:Methacrylates; C428805:OptiBond SOLO; C092987:Optibond; D011108:Polymers; D019279:Resin Cements; C084018:Scotchbond Multi-Purpose; C115612:single bond; C074811:Tenure adhesive; C100742:All-Bond 2; D017438:Bisphenol A-Glycidyl Methacrylate