title: Effect of phosphoric acid on the degradation of human dentin matrix.
abstract: This study determined if dentin proteases are denatured by phosphoric acid (PA) used in etch-and-rinse dentin adhesives. Dentin beams were completely demineralized with EDTA for 30 days. We "acid-etched" experimental groups by exposing the demineralized dentin beams to 1, 10, or 37 mass% PA for 15 sec or 15 min. Control beams were not exposed to PA but were incubated in simulated body fluid for 3 days to assay their total endogenous telopeptidase activity, by their ability to solubilize C-terminal crosslinked telopeptides ICTP and CTX from insoluble dentin collagen. Control beams released 6.1 ± 0.8 ng ICTP and 0.6 ± 0.1 ng CTX/mg dry-wt/3 days. Positive control beams pre-incubated in p-aminophenylmercuric acetate, a compound known to activate proMMPs, released about the same amount of ICTP peptides, but released significantly less CTX. Beams immersed in 1, 10, or 37 mass% PA for 15 sec or 15 min released amounts of ICTP and CTX similar to that released by the controls (p > 0.05). Beams incubated in galardin, an MMP inhibitor, or E-64, a cathepsin inhibitor, blocked most of the release of ICTP and CTX, respectively. It is concluded that PA does not denature endogenous MMP and cathepsin activities of dentin matrices.
authors.affiliation: Adhesive Dentistry Research Group, Institute of Dentistry, University of Turku, Turku, Finland.
authors.forename: A
authors.initials: A
authors.lastname: Tezvergil-Mutluay
authors.forename: M
authors.initials: M
authors.lastname: Mutluay
authors.forename: R
authors.initials: R
authors.lastname: Seseogullari-Dirihan
authors.forename: K A
authors.initials: KA
authors.lastname: Agee
authors.forename: W O
authors.initials: WO
authors.lastname: Key
authors.forename: D L S
authors.initials: DL
authors.lastname: Scheffel
authors.forename: L
authors.initials: L
authors.lastname: Breschi
authors.forename: A
authors.initials: A
authors.lastname: Mazzoni
authors.forename: L
authors.initials: L
authors.lastname: Tjäderhane
authors.forename: Y
authors.initials: Y
authors.lastname: Nishitani
authors.forename: F R
authors.initials: FR
authors.lastname: Tay
authors.forename: D H
authors.initials: DH
authors.lastname: Pashley
mesh_terms: D002403:Cathepsins / Q000037:antagonists & inhibitors; D024042:Collagen Type I / Q000032:analysis; D017364:Collagenases / Q000187:drug effects; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D003804:Dentin / Q000187:drug effects* / Q000201:enzymology; D004151:Dipeptides / Q000494:pharmacology; D020536:Enzyme Activators / Q000494:pharmacology; D004792:Enzyme Precursors / Q000187:drug effects; D006801:Humans; D007930:Leucine / Q000031:analogs & derivatives / Q000494:pharmacology; D008422:Materials Testing; D061965:Matrix Metalloproteinase Inhibitors / Q000494:pharmacology; D020782:Matrix Metalloproteinases / Q000187:drug effects; D010447:Peptide Hydrolases / Q000187:drug effects; D010455:Peptides / Q000032:analysis; D010662:Phenylmercuric Acetate / Q000031:analogs & derivatives / Q000494:pharmacology; D010756:Phosphoric Acids / Q000494:pharmacology*; D011489:Protein Denaturation; D013439:Sulfhydryl Reagents / Q000494:pharmacology; D013997:Time Factors
chemical_list: D024042:Collagen Type I; D015853:Cysteine Proteinase Inhibitors; D004151:Dipeptides; D020536:Enzyme Activators; D004792:Enzyme Precursors; D061965:Matrix Metalloproteinase Inhibitors; C078131:N-(2(R)-2-(hydroxamidocarbonylmethyl)-4-methylpentanoyl)-L-tryptophan methylamide; D010455:Peptides; D010756:Phosphoric Acids; D013439:Sulfhydryl Reagents; C052929:collagen type I trimeric cross-linked peptide; C010024:4-aminophenylmercuriacetate; C030242:phosphoric acid; D002403:Cathepsins; D010447:Peptide Hydrolases; D017364:Collagenases; D020782:Matrix Metalloproteinases; D007930:Leucine; D010662:Phenylmercuric Acetate; C024974:E 64