title: Role of bonding agents in the repair of composite resin restorations.
abstract: Six commonly used composite resin materials and recommended bonding systems were tested to assess shear bond strength at the interface between aged and new composites with and without bonding. Test specimens were aged in water for 60 d before new composite was placed. Shear bond strength was assessed after 22 ± 2 h (Test 1) and after additional ageing by thermocycling (5-55°C/5,000 cycles) (Test 2). After an additional 180 d in water, the aged specimens were randomly divided into three groups to blind the test with respect to the aged composite. New composites were placed on aged specimens (two groups with and one without bonding agent) and thermocycled (Test 3). After 24 h (Test 1), the mean shear bond strength of the test specimens was 21-26 MPa when bonding agents were used, as opposed to 10-15 MPa without bonding agents. After thermocycling (Test 2), the mean shear bond strength was 16-23 MPa with a bonding agent and 17 MPa without a bonding agent. After 180 d in water and subsequent thermocycling (Test 3), the mean shear bond strength was 9-13 MPa with bonding agent and 2-3 MPa when no bonding agent was used. The results of this study therefore indicate that the use of bonding agents significantly improves the quality of composite repair.
authors: Department of Cariology and Geriodontology, Faculty of Dentistry, University of Oslo, Oslo, Norway. frode.staxrud@odont.uio.no
authors: Frode
authors: F
authors: Staxrud
authors: Jon E
authors: JE
authors: Dahl
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry*; D003764:Dental Materials / Q000737:chemistry*; D058250:Dental Restoration Repair / Q000379:methods*; D017220:Dentin-Bonding Agents / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D019279:Resin Cements / Q000737:chemistry; D033081:Shear Strength; D062047:Silorane Resins; D012833:Siloxanes / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D000180:Acrylic Resins; C489662:AdheSE cement; C520091:CeramX; C084111:Charisma composite resin; D003188:Composite Resins; D003738:Dental Cements; D003764:Dental Materials; D017220:Dentin-Bonding Agents; C474035:Filtek Supreme; C444701:Filtek Z250; D008689:Methacrylates; D019279:Resin Cements; C084018:Scotchbond Multi-Purpose; D062047:Silorane Resins; D012833:Siloxanes; C501891:Tetric EvoCeram; C487957:Xeno III; C555513:silorane composite resin; D014867:Water; C041330:Scotchbond