Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
25
pubmed:dateCreated
2006-5-22
pubmed:abstractText
Auto-degradation of collagen matrices occurs in resin-infiltrated dentine by the slow action of host-derived matrix metalloproteinases. As phosphoric acid-etching inactivates these endogenous enzymes, it is puzzling how hybrid layers created by simplified etch-and-rinse adhesives can degrade in vivo. This study tested the null hypothesis that there are no differences in the relative proteolytic activities of mineralised dentine, acid-etched dentine, and etch-and-rinse adhesive-treated acid-etched dentine. Powdered dentine prepared from extracted human teeth was treated with 17% EDTA, 10% phosphoric acid, or with five simplified etch-and-rinse adhesives that were applied to 10% phosphoric acid-etched dentine. The gelatinolytic activity of the dentine powder was assayed using fluorescein-labelled gelatine. TEM examination of the air-dried, treated dentine powder was performed to confirm the presence of remnant mineralised dentine after acid-etching. 17% EDTA significantly reduced the relative proteolytic activity (73.2%) of the untreated mineralised dentine powder (control), while 10% phosphoric acid-etched dentine exhibited the highest reduction (98.1%). Treating the acid-etched dentine powder with any of the five simplified etch-and-rinse adhesives resulted in the reactivation of the proteolytic activity, with a significant negative linear correlation (P<0.05) between the increases in fluorescence and the corresponding pH values of the adhesives. It is concluded that simplified etch-and-rinse adhesives can reactivate endogenous enzymatic activities in dentine that are previously inactivated by phosphoric acid-etching. The amount of enzyme reactivated may even exceed the original quantity present in untreated mineralised dentine. This provides an explanation for the degradation of hybrid layers after acid-etched dentine matrices are infiltrated with these adhesives.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0142-9612
pubmed:author
pubmed:issnType
Print
pubmed:volume
27
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4470-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Reactivation of inactivated endogenous proteolytic activities in phosphoric acid-etched dentine by etch-and-rinse adhesives.
pubmed:affiliation
Department of SAU and FAL, University of Bologna, Bologna, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural