Linked Life Data

15212928

Source:http://linkedlifedata.com/resource/pubmed/id/15212928

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2004-6-23
pubmed:abstractText
Teeth contain several calcified tissues with junctions that provide interfaces between dissimilar tissues. These junctions have been difficult to characterize because of their small size. In this work a new technique using a combination of atomic force microscopy (AFM) and a force-displacement transducer was used to simultaneously study the surface topography and map mechanical properties of the junctions and adjacent hard tissues. Prepared specimens from human third molars were scanned by an AFM piezo-tube in contact mode. To measure the dynamic viscoelastic properties of the material a small sinusoidal force was superimposed on the contact force and the resulting displacement amplitude and the phase shift between the force and amplitude were measured. This force modulation technique was used to map the local variation of nanomechanical properties of intertubular dentin, peritubular dentin, enamel, dentin-enamel junction (DEJ) and peritubular-intertubular dentin junction (PIJ). This new technique allowed us to measure the widths of these junctions in addition to local variation in dentin and enamel without causing plastic deformation to the material and with 2 orders of magnitude increase in spatial resolution compared with previous studies that used discrete nanoindentation techniques. Due to the ability to analyze the sample line-by-line, the distribution functions associated with the width of the DEJ and PIJ were conveniently obtained for specific intratooth locations. The data suggested, for three third molar specimens, a DEJ width of 2-3 microm with full-width half-maximum (FWHM) of 0.7 microm and PIJ width of 0.5-1.0 microm with 0.3 microm FWHM. The intertubular dentin storage modulus variation was between 17 and 23 GPa with a mean value of 21 GPa. The range of storage modulus for enamel near the DEJ was between 51 and 74 GPa with a mean value of 63 GPa.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9290
pubmed:author
pubmed:issnType
Print
pubmed:volume
37
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1223-32
pubmed:dateRevised
2009-11-11
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Evaluation of a new modulus mapping technique to investigate microstructural features of human teeth.
pubmed:affiliation
Department of Preventive and Restorative Dental Sciences, University of California, San Francisco, Box 0758, D 2260 San Francisco, CA 94143-0758, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.