title: Histomorphologic characterization of noncarious and caries-affected dentin/adhesive interfaces.
abstract: OBJECTIVE
  The purpose of this study was to compare the dentin/adhesive interfacial characteristics when bonding to noncarious as well as caries-affected dentin.
  
  
  METHODS
  Seven extracted, unerupted, third molars were sectioned into halves. Artificial caries was created on one-half of each tooth, leaving the other half as a control. Dentin surfaces were treated with UNO adhesive according to the manufacturer's instructions for the wet-bonding technique and under environmental conditions present in the oral cavity. Dentin/adhesive interface sections of each half-tooth were stained with Goldner's trichrome, a classic bone stain, and examined using light microscopy. The width of exposed collagen was measured directly from photomicrographs, and adhesive penetration was analyzed qualitatively.
  
  
  RESULTS
  The degree and extent to which the adhesive encapsulated the demineralized dentin matrix were reflected in the color difference in the stained sections with the noncarious dentin sections showing a degree of collagen encapsulation superior to that of the caries-affected dentin sections. The overall mean widths of exposed collagen were significantly (p < or = .05) greater at the caries-affected dentin/adhesive interface, 8.6 (1.7) microm, as compared with those at the noncarious dentin/adhesive interface, 6.0 (1.5) microm.
  
  
  CONCLUSIONS
  The morphologic characteristics of the caries-affected dentin/interface suggest an increase in the exposed collagen zone and a decrease in the quality of the adhesive infiltration when compared with noncarious dentin. The evidence suggests that dentin substrate characteristics have a significant effect on the dentin/adhesive interface structure.
authors.affiliation: Department of Restorative Dentistry, School of Dentistry, Kansas City, MO 64108, USA. haj-alir@umkc.edu
authors.forename: Reem
authors.initials: R
authors.lastname: Haj-Ali
authors.forename: Mary
authors.initials: M
authors.lastname: Walker
authors.forename: Karen
authors.initials: K
authors.lastname: Williams
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.forename: Paulette
authors.initials: P
authors.lastname: Spencer
mesh_terms: D001565:Benzoates / Q000737:chemistry*; D001840:Dental Bonding / Q000379:methods*; D003731:Dental Caries / Q000150:complications* / Q000628:therapy; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D006801:Humans; D008689:Methacrylates / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D001565:Benzoates; D017220:Dentin-Bonding Agents; D008689:Methacrylates; C080129:pyromellitic dianhydride glycerol dimethacrylate adduct