Ändra sökning
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Effect of light power density variations on bulk curing properties of dental composites
Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Maskinelement.ORCID-id: 0000-0001-8676-8819
Luleå tekniska universitet.
2003 (Engelska)Ingår i: Journal of Dentistry, ISSN 0300-5712, E-ISSN 1879-176X, Vol. 31, nr 3, s. 189-196Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Objective. The hypothesis that low light intensity and long but sufficient curing time can produce composites with volumetric shrinkage, degree of conversion (DC%) and Young's modulus (E-modulus) comparable to those of high light intensity cured composite was tested, when the contraction strain and heat generation were lower with low light intensity curing. Methods. Dental composites (Z100 and Z250, 3M ESPE) were investigated. Specimens were cured with light intensities of 200, 450 and 800 mW/cm2 for 140, 60 and 35 s from a distance of 7 mm. Strain-gages were used for contraction strain measurements. DC% was measured at the top and the bottom of 4 mm thick samples using FT-Raman spectroscopy. Volumetric polymerization shrinkage was determined using a water displacement method. E-modulus was determined in tension on composite specimens. Results. The results were analyzed using ANOVA and Duncan's multiple range tests and regular t-test. Polymerization stress level decreased significantly (p<0.05) when cured with 200 mW/cm2 rather than with 800 mW/cm2. Temperature rises were significantly different (p<0.05) for different composites and light intensity values. Reduction in light intensity did not decrease the DC% values significantly at the top surfaces. The most dramatic differences existed between top and bottom surfaces (p<0.05) rather than among curing groups. Measured E-modulus and volumetric shrinkage values were not significantly different (p>0.05) between different light intensity groups. Conclusion. DC%, E-modulus and the volumetric shrinkage values in cured composites were not affected by low light intensity, however, the contraction strain and polymerization's exotherm were decreased. Thus our results support the proposed hypothesis.

Ort, förlag, år, upplaga, sidor
2003. Vol. 31, nr 3, s. 189-196
Nationell ämneskategori
Tribologi (ytteknik omfattande friktion, nötning och smörjning) Kompositmaterial och -teknik
Forskningsämne
Maskinelement; Polymera konstruktionsmaterial
Identifikatorer
URN: urn:nbn:se:ltu:diva-9910DOI: 10.1016/S0300-5712(03)00015-0ISI: 000182878600005Scopus ID: 2-s2.0-0038378492Lokalt ID: 89d283f0-e80f-11db-b9a9-000ea68e967bOAI: oai:DiVA.org:ltu-9910DiVA, id: diva2:982849
Anmärkning
Validerad; 2003; 20070411 (ysko)Tillgänglig från: 2016-09-29 Skapad: 2016-09-29 Senast uppdaterad: 2018-07-10Bibliografiskt granskad

Open Access i DiVA

Fulltext saknas i DiVA

Övriga länkar

Förlagets fulltextScopus

Personposter BETA

Emami, Nazanin

Sök vidare i DiVA

Av författaren/redaktören
Emami, Nazanin
Av organisationen
Maskinelement
I samma tidskrift
Journal of Dentistry
Tribologi (ytteknik omfattande friktion, nötning och smörjning)Kompositmaterial och -teknik

Sök vidare utanför DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetricpoäng

doi
urn-nbn
Totalt: 70 träffar
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf