Impact of the light-curing source and curing time on the degree of conversion and hardness of a composite

Authors

  • Anderson Catelan University of Campinas
  • Caetano Tamires University of Campinas
  • Boniek Castillo Dutra Borges Potiguar University
  • Giulliana Panfiglio Soares University of Campinas
  • Bruno de Castro Ferreira Barreto Federal University of Uberlandia
  • Natália Maria Aparecida Pinto Hernandes University of Campinas
  • Maria Cecília Caldas Giorgi University of Campinas
  • Flávio Henrique Baggio Aguiar University of Campinas

DOI:

https://doi.org/10.19177/jrd.v1e1201391-97

Keywords:

Composites resins, Physical properties, Hardness

Abstract

Adequate physical properties of the resinous materials are related to clinical longevity of adhesive restorations. The aim of this investigation was to assess the impact of light-curing source and curing time on the degree of conversion (DC) and Knoop hardness number (KHN) of a composite resin. Circular specimens (5 x 2 mm) were carried out (n = 7) of the Filtek Z250 (3M ESPE) composite. The specimens were light-cured by quartz-halogen-tungsten (QTH) XL 3000 (3M ESPE, 450 mW/cm2) or light-emitting diode (LED) Bluephase 16i (Vivadent, 1390 mW/cm2) for 20, 40, or 60 s. After 24 h, absorption spectra of composite were obtained using Spectrum 100 Optica (Perkin Elmer) FT-IR spectrometer in order to calculate the DC and, KHN was performed in the HMV-2T (Shimadzu) microhardness tester under 50-g load for 15 s dwell time. DC and KHN data were subjected to 2-way ANOVA and Tukey’s test at a pre-set alpha of 0.05. The LED showed highest DC and KHN values than QTH (p < 0.05). The increase of curing time improved the DC and KHN, all curing times with statistical difference (p < 0.05). The use of light-curing units with high irradiance and/or the time of cure increased may improve the physical properties of resin-based materials.

Author Biographies

  • Anderson Catelan, University of Campinas
    DDS, MS, PhD in progress. Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, SP, Brazil
  • Caetano Tamires, University of Campinas
    Undergraduate. Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, SP, Brazil
  • Boniek Castillo Dutra Borges, Potiguar University
    DDS, MS, Assistant Professor, Potiguar University (Laureate International Universities), Natal, RN, Brazil
  • Giulliana Panfiglio Soares, University of Campinas
    DDS, MS, PhD in progress. Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, SP, Brazil
  • Bruno de Castro Ferreira Barreto, Federal University of Uberlandia
    DDS, MS, PhD, Pos-Doc in progress. Department of Operative Dentistry and Dental Materials, Dental School, Federal University of Uberlandia, Uberlandia, MG, Brazil
  • Natália Maria Aparecida Pinto Hernandes, University of Campinas
    DDS, MS, PhD in progress. Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, SP, Brazil
  • Maria Cecília Caldas Giorgi, University of Campinas
    DDS, MS, PhD, Pos-Doc in progress. Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, SP, Brazil
  • Flávio Henrique Baggio Aguiar, University of Campinas
    DDS, MS, PhD, Assistant Professor. Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, SP, Brazil

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Published

2013-04-23

Issue

Vol. 1 No. 1 (2013)

Section

Articles

License

CC Attribution-NonCommercial-NoDerivatives 4.0