title: Assessing Collagen and Micro-permeability at the Proanthocyanidin-treated Resin-Dentin Interface.
abstract: OBJECTIVE
  To establish a fluorescence-based method to simultaneously assess micro-permeability and collagen cross-linking induced by chemical agents at the resin-dentin interface.
  
  
  METHODS
  Three chemical agents were investigated (proanthocyanidin-rich grape seed extract: GSE; carbodiimide hydrochloride/N-hydroxysuccinimide: EDC/NHS; glutaraldehyde: GD) along with a control (distilled water) as primers applied on flat occlusal dentin surfaces of 48 teeth and restored with two commercially available etch-and-rinse adhesives. Resin-dentin interfaces were polished and infiltrated with rhodamine-B solution for confocal laser scanning microscopy analysis. Parameters were chosen that would allow acquisition of a simultaneous appearance of collagen and interfacial micro-permeability (rhodamine-B). Fluorescence emission intensity (FEI) was converted into numerals and values were calculated for each group. Data were statistically analyzed using one-way ANOVA and post-hoc Scheffe's and multiple comparisons tests (α = 0.05). T-tests with Pearson correlations were used to investigate correlations between collagen cross-linking and micro-permeability.
  
  
  RESULTS
  The FEI of collagen was the highest for GD, followed by GSE, with no significant differences between EDC/ NHS and the control group (p > 0.05). Micro-permeability was significantly affected by the adhesives (p < 0.05). Micro- permeability was the lowest for GSE groups, regardless of the adhesives (p < 0.001). Weak correlations were found between micro-permeability and collagen auto-fluorescence.
  
  
  CONCLUSIONS
  Non-enzymatic collagen cross-linking induced by GSE and GD can be detected by increased collagen auto-fluorescence, and results in reduced interfacial micro-permeability. Increased collagen auto-fluorescence was correlated with fluorescent collagen cross-links and decreased micro-permeability at the resin-dentin interface. Collagen auto-fluorescence is a useful tool to detect auto-fluorescent exogenous cross links and their potential impact on the quality of the resin-dentin interface.
authors.forename: Berdan
authors.initials: B
authors.lastname: Aydin
authors.forename: Lina Saleh
authors.initials: LS
authors.lastname: Hassan
authors.forename: Grace
authors.initials: G
authors.lastname: Viana
authors.forename: Ana K
authors.initials: AK
authors.lastname: Bedran-Russo
mesh_terms: D003094:Collagen / Q000378:metabolism*; D003432:Cross-Linking Reagents / Q000494:pharmacology; D003804:Dentin / Q000187:drug effects; D006801:Humans; D010539:Permeability / Q000187:drug effects; D044945:Proanthocyanidins / Q000494:pharmacology*; D012117:Resins, Synthetic
chemical_list: D003432:Cross-Linking Reagents; D044945:Proanthocyanidins; D012117:Resins, Synthetic; C013221:proanthocyanidin; D003094:Collagen