title: Effect of carbamide peroxide bleaching on the shear bond strength of composite to dental bonding agent enhanced enamel.
abstract: BACKGROUND
  Carbamide peroxide bleaching has been implicated in adversely affecting the bond strength of composite to enamel.
  
  
  OBJECTIVE
  This in vitro study evaluated the effect of 3 dental bonding agents (OptiBond, All-Bond 2, One-Step) on the shear bond strength of a hybrid composite to enamel which was treated by a 10% carbamide peroxide bleaching system.
  
  
  METHODS
  Cylinders of composite were bonded to carbamide peroxide-treated enamel on extracted human teeth using 3 dental bonding agents. After thermocycling, shear bond strengths were determined with a universal testing machine.
  
  
  RESULTS
  OptiBond aided bond strengths were 23.7 +/- 5.6 MPa to bleached and 19.6 +/- 2.9 MPa to unbleached enamel. For All-Bond 2, bleached enamel exhibited bond strengths of 14.9 +/- 4.0 MPa and unbleached enamel exhibited a bond strength value of 20. 4 +/- 2.3 MPa. The composite bond strength for One-Step was 13.6 +/- 5.9 MPa to bleached and 23.0 +/- 3.9 MPa to unbleached enamel. There was no statistical difference between OptiBond (alcohol base) aided bond strengths for bleached and unbleached enamel; however, the bond strength of composite to bleached enamel with All-Bond 2 or One-Step (acetone base) was significantly lower than unbleached controls.
  
  
  CONCLUSIONS
  The effect of bonding agent usage on composite bond strength to enamel bleached with a particular carbamide peroxide was dependent on the bonding agent used.
authors.affiliation: School of Dentistry, University of California at Los Angeles, CA 90095-1668, USA. ericsung@ucla.edu
authors.forename: E C
authors.initials: EC
authors.lastname: Sung
authors.forename: S M
authors.initials: SM
authors.lastname: Chan
authors.forename: R
authors.initials: R
authors.lastname: Mito
authors.forename: A A
authors.initials: AA
authors.lastname: Caputo
mesh_terms: D000704:Analysis of Variance; D000077463:Carbamide Peroxide; D003188:Composite Resins / Q000494:pharmacology*; D001840:Dental Bonding; D003743:Dental Enamel / Q000187:drug effects*; D017220:Dentin-Bonding Agents / Q000494:pharmacology*; D004338:Drug Combinations; D006801:Humans; D066298:In Vitro Techniques; D008422:Materials Testing / Q000379:methods / Q000706:statistics & numerical data; D008689:Methacrylates / Q000494:pharmacology*; D008963:Molar; D010545:Peroxides / Q000494:pharmacology*; D019279:Resin Cements / Q000494:pharmacology*; D013718:Tensile Strength / Q000187:drug effects; D014073:Tooth Bleaching / Q000379:methods*; D014508:Urea / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: C103506:Bis-GMA, BPDM, HEMA dental-bonding resin; D003188:Composite Resins; D017220:Dentin-Bonding Agents; D004338:Drug Combinations; D008689:Methacrylates; C092987:Optibond; D010545:Peroxides; D019279:Resin Cements; C100742:All-Bond 2; D000077463:Carbamide Peroxide; D014508:Urea