title: Single-step, self-etch adhesives behave as permeable membranes after polymerization. Part III. Evidence from fluid conductance and artificial caries inhibition.
abstract: OBJECTIVE
  To test the hypothesis that formation of inhibition zones by bonded restorations in artificially-induced carious dentin lesions is related to the permeability of the self-etch adhesives.
  
  
  METHODS
  Fluid conductance of four single-step self-etch adhesives (Prompt L-Pop, Etch&Prime 3.0, One-Up Bond F and Reactmer Bond), and a control two-step self-etch adhesive (UniFil Bond) were measured after sound dentin surfaces were:(1) acid-etched; (2) polished to produce smear layers; (3) bonded with the adhesive; each at 20 cm hydrostatic pressure (hp). Osmotic fluid conductance was also determined for the bonded dentin after immersion in 4.8 M CaCl2 at 0 cm hp. For artificial caries inhibition, a non-fluoride releasing (NFR) two-step self-etch adhesive (UniFil Bond) and a fluoride-releasing (FR) single-step adhesive (Reactmer Bond) were used in combination with a NFR composite (Metafil CX) or a FR restorative material (Reactmer Paste). Artificial caries were induced in these restorations, from which 120 +/- 10 microm thick sections and the effect of caries inhibition were quantitatively assessed with polarizing light microscopy and image analysis.
  
  
  RESULTS
  Fluid conductance after bonding with the single-step adhesives Prompt L-Pop and Etch&Prime 3.0 were not significantly different from those recorded from smear layer-covered dentin. Although better seals were achieved with One-Up Bond F and Reactmer Bond, fluid conductance at 20 cm hp was significantly higher than the two-step self-etch adhesive UniFil Bond. Osmotic conductance at 0 cm hp were not significantly different from normal fluid conductance at 20 cm hp. The sizes of artificial carious lesions in UniFil Bond were significantly higher irrespective of whether a FR or NFR composite was used. Significant reduction in lesion size occurred in Reactmer Bond with the use of a NFR composite, and even more so with the use of a FR composite.
authors.affiliation: Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China.
authors.forename: Anut
authors.initials: A
authors.lastname: Itthagarun
authors.forename: Franklin R
authors.initials: FR
authors.lastname: Tay
authors.forename: David H
authors.initials: DH
authors.lastname: Pashley
authors.forename: James S
authors.initials: JS
authors.lastname: Wefel
authors.forename: Franklin
authors.initials: F
authors.lastname: García-Godoy
authors.forename: Stephen H Y
authors.initials: SH
authors.lastname: Wei
mesh_terms: D000134:Acid Etching, Dental; D002327:Cariostatic Agents / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003731:Dental Caries / Q000473:pathology / Q000517:prevention & control*; D003804:Dentin / Q000378:metabolism; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D000431:Ethanol / Q000737:chemistry; D005459:Fluorides / Q000737:chemistry; D005899:Glass Ionomer Cements / Q000737:chemistry; D006801:Humans; D006874:Hydrostatic Pressure; D008422:Materials Testing; D008560:Membrane Fluidity; D008567:Membranes, Artificial; D008689:Methacrylates / Q000737:chemistry; D009995:Osmosis; D010539:Permeability; D010710:Phosphates / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D012212:Rheology; D016369:Smear Layer
chemical_list: D002327:Cariostatic Agents; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C469823:Etch&Prime 3.0; D005899:Glass Ionomer Cements; D008567:Membranes, Artificial; C495852:Metafil C; D008689:Methacrylates; C446260:One-Up-Bond F; D010710:Phosphates; C408584:Prompt L-Pop; D019279:Resin Cements; C407402:Unifil Bond; C447779:reactmer bond; D000431:Ethanol; D005459:Fluorides