The effect of various surface treatments and bonding agents on the repaired strength of heat-treated composites.
BACKGROUND
Some clinical situations may require the repair of a secondary polymerized or aged composite. The higher indirect resin conversion rate may prove to be a disadvantage if a repair procedure based on covalent bonding from unreacted methacrylate groups is attempted.


OBJECTIVE
This study evaluated the effectiveness of different combinations of surface treatments and 2 bonding agents used to enhance heat-polymerized and aged composite repairs.


METHODS
Ninety Herculite XRV and 90 Heliomolar Radiopaque specimens were prepared and then postpolymerized and stored for 4 weeks. All composites were subjected to 1 of 9 treatment regimens that involved adding fresh composite onto a corresponding postpolymerized composite (Herculite/Herculite or Heliomolar/Heliomolar). The surfaces were treated with different combinations of air abrasion, phosphoric acid, hydrofluoric acid, acetone, Special Bond II, Heliobond, and Prime & Bond 2.0.


RESULTS
Surface treatment with air abrasion resulted in the strongest repairs; surface treatment with phosphoric acid resulted in the weakest repairs.


CONCLUSIONS
The use of air abrasion and Prime & Bond 2.0 adhesive consistently improved the shear bond strength for both composites tested.
Lucena-Martín
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C
Faculty of Dentistry, University of Granada, Granada, Spain. clucena@terra.es
González-López
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Navajas-Rodríguez de Mondelo
J M
JM
D000096:Acetone / Q000737:chemistry; D000134:Acid Etching, Dental; D000179:Acrylates / Q000737:chemistry; D000180:Acrylic Resins / Q000737:chemistry; D000268:Adhesiveness; D000704:Analysis of Variance; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry; D017220:Dentin-Bonding Agents / Q000737:chemistry; D006358:Hot Temperature; D006801:Humans; D006858:Hydrofluoric Acid / Q000737:chemistry; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D010756:Phosphoric Acids / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D011140:Polyurethanes / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013223:Statistics as Topic; D013314:Stress, Mechanical; D013499:Surface Properties
D000179:Acrylates; D000180:Acrylic Resins; C029012:Composite Dental Resin; D003188:Composite Resins; D003738:Dental Cements; D017220:Dentin-Bonding Agents; C513708:Heliomolar; D008689:Methacrylates; D010756:Phosphoric Acids; D011108:Polymers; D011109:Polymethacrylic Acids; D011140:Polyurethanes; C103500:Prime & Bond; D019279:Resin Cements; D012997:Solvents; C086660:Special Bond 2 dental cement; C065770:Herculite XR; D000096:Acetone; D017438:Bisphenol A-Glycidyl Methacrylate; C040415:heliobond; D006858:Hydrofluoric Acid