The change of the initial dynamic visco-elastic modulus of composite resins during light polymerization

Min-Ho Kim; In-Bog Lee

doi:10.5395/JKACD.2009.34.5.450

Articles

Page Path: HOME > Restor Dent Endod > Volume 34(5); 2009 > Article

Original Article The change of the initial dynamic visco-elastic modulus of composite resins during light polymerization: Min-Ho Kim, In-Bog Lee; Journal of Korean Academy of Conservative Dentistry 2009;34(5):450-459.
DOI: https://doi.org/10.5395/JKACD.2009.34.5.450
Published online: September 30, 2009

Department of Conservative Dentistry, School of Dentistry, Seoul National University, Korea.

Corresponding Author: In-Bog Lee. Department of Conservative Dentistry School of Dentistry, Seoul National University 275-1, Yeongeon-dong, Jongno-gu, 110-768, Korea. Tel: 82-2-2072-3953, Fax: 82-2-2072-3859, inboglee@snu.ac.kr

• Received: May 6, 2009 • Revised: June 18, 2009 • Accepted: July 9, 2009

22 Views
0 Download

prev next

Full Article

Download PDF

Abstract
REFERENCES

Abstract

The aim of this study was to measure the initial dynamic modulus changes of light cured composites using a custom made rheometer. The custom made rheometer consisted of 3 parts: (1) a measurement unit of parallel plates made of glass rods, (2) an oscillating shear strain generator with a DC motor and a crank mechanism, (3) a stress measurement device using an electromagnetic torque sensor. This instrument could measure a maximum torque of 2Ncm, and the switch of the light-curing unit was synchronized with the rheometer.

Six commercial composite resins [Z-100 (Z1), Z-250 (Z2), Z-350 (Z3), DenFil (DF), Tetric Ceram (TC), and Clearfil AP-X (CF)] were investigated. A dynamic oscillating shear test was undertaken with the rheometer. A certain volume (14.2 mm³) of composite was loaded between the parallel plates, which were made of glass rods (3 mm in diameter). An oscillating shear strain with a frequency of 6 Hz and amplitude of 0.00579 rad was applied to the specimen and the resultant stress was measured. Data acquisition started simultaneously with light curing, and the changes in visco-elasticity of composites were recorded for 10 seconds. The measurements were repeated 5 times for each composite at 25±0.5℃. Complex shear modulus G^*, storage shear modulus G', loss shear modulus G" were calculated from the measured strain-stress curves. Time to reach the complex modulus G^* of 10 MPa was determined. The G^* and time to reach the G^* of 10 MPa of composites were analyzed with One-way ANOVA and Tukey's test (α= 0.05).

The results were as follows.

1. The custom made rheometer in this study reliably measured the initial visco-elastic modulus changes of composites during 10 seconds of light curing.

2. In all composites, the development of complex shear modulus G^* had a latent period for 1~2 seconds immediately after the start of light curing, and then increased rapidly during 10 seconds.

3. In all composites, the storage shear modulus G' increased steeper than the loss shear modulus G" during 10 seconds of light curing.

4. The complex shear modulus of Z1 was the highest, followed by CF, Z2, Z3, TC and DF the lowest.

5. Z1 was the fastest and DF was the slowest in the time to reach the complex shear modulus of 10 MPa.
Keywords: Light cured composites; Visco-elastic modulus; Rheometer; Dynamic oscillating shear test; Complex shear modulus

REFERENCES

1. Dauvillier BS, Feilzer AJ, De Gee AJ, Davison CL. Visco-elastic parameters of dental restorative materials during setting. J Dent Res. 2000;79(3):818-823.Article PubMed PDF
2. Guggenberger R, Weinmann W. Exploring beyond methacrylates. Am J Dent. 2000;13: 82D-84D.PubMed
3. Ellakwa A, Cho N, Lee IB. The effect of resin matrix composition on the polymerization shrinkage and rheological properties of experimental dental composites. Dent Mater. 2007;23: 1229-1235.Article PubMed
4. Labella R, Lambrechts P, Van Meerbeek B, Vanherle G. Polymerization shrinkage and elasticity of flowable composites and filled adhesives. Dent Mater. 1999;15: 128-137.Article PubMed
5. Braga RR, Ferracane JL. Contraction stress related to degree of conversion and reaction kinetics. J Dent Res. 2002;81: 114-118.Article PubMed PDF
6. Kleverlaan CJ, Feilzer AJ. Polymerization shrinkage and contraction stress of dental resin composites. Dent Mater. 2005;21: 1150-1157.PubMed
7. Feilzer AJ, De Gee AJ, Davison CL. Setting stress in composite resin in relation to configuration of the restoration. J Dent Res. 1987;66: 1636-1369.Article PubMed PDF
8. Charton C, Colon P, Pla F. Shrinkage stress in light-cured composite resins:Influence of material and photoactivation mode. Dent Mater. 2007;23: 911-920.Article PubMed
9. Odian G. Principles of polymerization. 1991;3rd Ed. New York: John Wiley & Sons, Inc.; 216-226.
10. Sakaguchi RL, Shah NC, Lim BS, Ferracane JL, Borgersen SE. Dynamic mechanical analysis of storage modulus development in light-activated polymer matrix composites. Dent Mater. 2002;18: 197-202.Article PubMed
11. Mesquita RV, Axmann D, Geis-Gerstorfer J. Dynamic visco-elastic properties of dental composite resins. Dent Mater. 2006;22: 258-267.PubMed
12. Helvatjoglu-Antoniades M, Papadogiannis Y, Lakes RS, Dionysopoulos P, Papadogiannis D. Dynamic and static elastic moduli of packable and flowable composite resins and their development after initial photo curing. Dent Mater. 2006;22: 450-459.Article PubMed
13. Nakayama WT, Hall DR, Grenoble DE, Katz JL. Elastic properties of dental resin restorative materials. J Dent Res. 1974;53: 1121-1126.Article PubMed PDF
14. Braem M, Lambrechts P, Van Doren V, Vanherle G. The impact of composite structure on its elastic response. J Dent Res. 1986;65: 648-653.Article PubMed PDF
15. Lee IB, Son HH, Um CM. Rheologic properties of flowable, conventional hybrid, and condensable composite resins. Dent Mater. 2003;19: 298-307.PubMed
16. Lee IB, Cho BH, Son HH, Um CM. Rheological characterization of composites using a vertical oscillation rheometer. Dent Mater. 2007;23: 425-432.Article PubMed
17. Suh HY, Lee IB. Slumping resistance and viscoelasticity of resin composite pastes. J Korean Acad Conserv Dent. 2008;33: 235-245.Article
18. Braem M, Lambrechts P, Vanherle G, Davidson CL. Stiffness increase during the setting of dental composite resins. J Dent Res. 1987;66(12):1713-1716.Article PubMed PDF
19. Sakaguchi RL, Wiltbank BD, Murchison CF. Prediction of composite elastic modulus and polymerization shrinkage by computational micromechanics. Dent Mater. 2004;20: 397-401.PubMed
20. Lee JH, Um CM, Lee IB. Rheological properties of resin composites according to variations in monomer and filler composition. Dent Mater. 2006;22: 515-526.Article PubMed
21. Tanimoto Y, Nishiwaki T, Nemoto K. Dynamic viscoelastic behavior of dental composites measured by split Hopkinson pressure bar. Dent Mater J. 2006;25(2):234-240.Article PubMed
22. Ferracane JL. Developing a more complete understanding of stresses produced in dental composites during polymerization. Dent Mater. 2005;21: 36-42.Article PubMed
23. Seo DG, Min SH, Lee IB. Effect of instrument compliance on the polymerization shrinkage stress measurements of dental resin composites. J Korean Acad Conserv Dent. 2009;34: 145-153.
24. Park JG, Lim BS, Lee IB. Cuspal deflection in class v cavities restored with composite resins. J Korean Acad Conserv Dent. 2008;33: 83-89.Article

Figure 1

Configuration of the custom made rheometer.

Figure 2

Circuit diagram of the instrument.

Figure 3

The relationship among shear strain γ(t), stress τ(t), and phase angle δ in a dynamic oscillatory test.

Figure 4

The relationship among storage (real) modulus G', loss (imaginary) modulus G", and phase angle δ in a complex plane.

Figure 5

Parallel plate geometry.

Figure 6

Representative strain-stress curves of composites during light curing as a function of time.

a. Z-100. b. Z-250. c. Z-350. d. DenFil. e. Tetric Ceram. f. Clearfil.

Figure 7

Complex modulus (G^*) of composites as a function of time.

Figure 8

Storage modulus (G') as a function of time.

Figure 9

Loss modulus (G") as a function of time.

Figure 10

Time to reach the complex modulus of 10 MPa.

Table 1

Composite resins used in this study.

Table 2

Time to reach G^* of 10 MPa, G^* and Loss tangent of composites at 2 s and 10 s.

^*Same superscripts in the column means no statistical significant difference.

Tables & Figures

REFERENCES

Citations

Citations to this article as recorded by

ePub Link

Cite

CITE: export Copy Download Format; Close

Download Citation

Download a citation file in RIS format that can be imported by all major citation management software, including EndNote, ProCite, RefWorks, and Reference Manager.

Format:

RIS — For EndNote, ProCite, RefWorks, and most other reference management software
BibTeX — For JabRef, BibDesk, and other BibTeX-specific software

Include:

Citation for the content below
Citation and abstract for the content below

The change of the initial dynamic visco-elastic modulus of composite resins during light polymerization

J Korean Acad Conserv Dent. 2009;34(5):450-459. Published online September 30, 2009

DOI: https://doi.org/10.5395/JKACD.2009.34.5.450

XML Download

Figure

The change of the initial dynamic visco-elastic modulus of composite resins during light polymerization

Figure 1 Configuration of the custom made rheometer.

Figure 2 Circuit diagram of the instrument.

Figure 3 The relationship among shear strain γ(t), stress τ(t), and phase angle δ in a dynamic oscillatory test.

Figure 4 The relationship among storage (real) modulus G', loss (imaginary) modulus G", and phase angle δ in a complex plane.

Figure 5 Parallel plate geometry.

Figure 6 Representative strain-stress curves of composites during light curing as a function of time. a. Z-100. b. Z-250. c. Z-350. d. DenFil. e. Tetric Ceram. f. Clearfil.

Figure 7 Complex modulus (G*) of composites as a function of time.

Figure 8 Storage modulus (G') as a function of time.

Figure 9 Loss modulus (G") as a function of time.

Figure 10 Time to reach the complex modulus of 10 MPa.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

The change of the initial dynamic visco-elastic modulus of composite resins during light polymerization

Table 1

Composite resins used in this study.

Table 2

Time to reach G^* of 10 MPa, G^* and Loss tangent of composites at 2 s and 10 s.

^*Same superscripts in the column means no statistical significant difference.

Table 1 Composite resins used in this study.

Table 2 Time to reach G* of 10 MPa, G* and Loss tangent of composites at 2 s and 10 s.

^*Same superscripts in the column means no statistical significant difference.