title: Bond strength of composite to sound and artificial carious dentin.
abstract: OBJECTIVE
  To determine the in vitro bond strength of a composite (Herculite XRV) to sound dentin and artificial carious lesions in dentin.
  
  
  METHODS
  Buccal and lingual surfaces from extracted human molar teeth were ground to expose sound dentin surfaces. The buccal surface was maintained as sound dentin, while an artificial carious lesion was created in the lingual surface using an acidified gelatin gel. A bonding agent (Optibond) was applied to both buccal and lingual surfaces with and without prior etching with 37.5% phosphoric acid. The composite was applied and debonded under tension after 24 hours in water at 37 degrees C.
  
  
  RESULTS
  Both sound dentin (23.1 MPa) and etched sound dentin (22.2 MPa) had similar bond strengths, whereas artificial carious lesions in dentin that had been etched (11.8 MPa) and non-etched dentin lesions (8.8 MPa) had significantly lower bond strengths. Adhesive failures were greatest for dentin lesions (60-95%) and least for sound dentin(40-50%). Etching with phosphoric acid did not improve the bond strength of composite to sound dentin or artificial carious lesions in dentin.
authors.affiliation: Department of Basic Sciences, University of Texas-Houston Health Science Center, USA.
authors.forename: J
authors.initials: J
authors.lastname: Xie
authors.forename: C M
authors.initials: CM
authors.lastname: Flaitz
authors.forename: M J
authors.initials: MJ
authors.lastname: Hicks
authors.forename: J M
authors.initials: JM
authors.lastname: Powers
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D000704:Analysis of Variance; D003188:Composite Resins; D001840:Dental Bonding / Q000379:methods; D003731:Dental Caries; D003804:Dentin / Q000473:pathology / Q000648:ultrastructure; D017220:Dentin-Bonding Agents; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010756:Phosphoric Acids; D019279:Resin Cements; D013718:Tensile Strength
chemical_list: D003188:Composite Resins; D017220:Dentin-Bonding Agents; C092987:Optibond; D010756:Phosphoric Acids; D019279:Resin Cements; C065770:Herculite XR; C030242:phosphoric acid