title: Dual application of dentin bonding agents: effect on bond strength.
abstract: OBJECTIVE
  To evaluate the effect of a dual application of dentin bonding agents (DBA) on their shear bond strength on dentin with intermediate application of a provisional cement.
  
  
  METHODS
  Freshly prepared flat dentin surfaces of human teeth were coated with a first layer of one of various dentin bonding agents (All-Bond 2, ART Bond, Syntac or an experimental DBA called P-Bond). After curing the DBA, a provisional cement (Temp Bond, Freegenol or Fermit, a soft provisional diacrylate) was applied to the bonded dentin surface. After 24 hours, the provisional cement was removed and the dentin surface scrubbed with pumice. A second application of the same DBA together with a composite cylinder followed. After curing and 1,500 thermal cycles with constant imitation of intrapulpal pressure, shear bond strengths were measured.
  
  
  RESULTS
  Compared to a single application of dentin bonding agents following Temp Bond treatment (SBS in MPa: Syntac: 0.86 +/- 1.75, ART Bond: 0.26 +/- 0.47, P-Bond: 14.90 +/- 4.51) application of DBAs prior to use of Temp Bond as well as after its removal seems to be very beneficial to shear bond strength values (SBS in MPa: Syntac:13.36 +/- 4.70, ART Bond: 16.34 +/- 5.02, P-Bond: 19.04 +/- 2.01). Independent from the provisional cement, the values after serial application of P-Bond provided consistently high bond values which were not statistically different (Kruskal-Wallis, P > 0.05) from values of P-Bond on fresh dentin (18.19 +/- 2.29 MPa). The only exception from these findings in the present study was All-Bond 2. Regardless of the provisional materials used, the bond strength values of All-Bond 2 remained low (maximum SBS with Fermit as intermediate provisional cement: 4.63 +/- 2.91 MPa).
authors.affiliation: Department of Fixed and Removable Prosthodontics and Dental Material Sciences, School of Dentistry, University of Zurich, Switzerland. stpaul@zui.unizh.ch
authors.forename: C
authors.initials: C
authors.lastname: Bertschinger
authors.forename: S J
authors.initials: SJ
authors.lastname: Paul
authors.forename: H
authors.initials: H
authors.lastname: Lüthy
authors.forename: P
authors.initials: P
authors.lastname: Schärer
mesh_terms: D002484:Cementation; D003188:Composite Resins; D001840:Dental Bonding / Q000379:methods*; D003738:Dental Cements; D003793:Dental Restoration, Permanent / Q000379:methods*; D003794:Dental Restoration, Temporary; D017220:Dentin-Bonding Agents; D005054:Eugenol; D006801:Humans; D008298:Maleates; D008422:Materials Testing; D008689:Methacrylates; D011109:Polymethacrylic Acids; D019279:Resin Cements; D018709:Statistics, Nonparametric; D013718:Tensile Strength; D015034:Zinc Oxide
chemical_list: C088247:ART Bond; C074864:All-Bond system; D003188:Composite Resins; D003738:Dental Cements; D017220:Dentin-Bonding Agents; C072654:Fermit; C078077:Freegenol; D008298:Maleates; D008689:Methacrylates; D011109:Polymethacrylic Acids; D019279:Resin Cements; C078484:Syntac dentine adhesive; D005054:Eugenol; C076899:Temp-Bond; D015034:Zinc Oxide