Abstract
Purpose
This study was designed to compare the amount of polymerization shrinkage of dual-cure resin cements according to different polymerization modes and to determine the effect of light activation on the degree of polymerization.
Materials and methods
Four kinds of dual-cure resin cements were investigated: Smartcem 2, Panavia F 2.0, Clearfil SA Luting and Zirconite. Each material was tested in three different polymerization modes: self-polymerization only, immediate light polymerization and 5 minutes-delayed light polymerization. The time-dependent polymerization shrinkage-strain was evaluated for 30 minutes by Bonded-disk method at 37°C. Five recordings of each material with three different modes were taken. Data were analyzed using one-way ANOVA and multiple comparison Scheffe′test (α =.05).
Results
All materials, except Panavia F 2.0, exhibited the highest polymerization shrinkage-strain through delayed light-activated polymerization. No significant difference between light activation modes was found with Panavia F 2.0. All materials exhibited more than 90% of polymerization rate in the immediate or delayed light activated group within 10 minutes.
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![]() | Fig. 1.Representative polymerization shrinkage-strain kinetic curves of Smartcem 2 for each curing mode. |
![]() | Fig. 2.Representative polymerization shrinkage-strain kinetic curves of Panavia F 2.0 for each curing mode. |
![]() | Fig. 3.Representative polymerization shrinkage-strain kinetic curves of Clearfil SA Luting for each curing mode. |
![]() | Fig. 4.Representative polymerization shrinkage-strain kinetic curves of Zirconite for each curing mode. |
![]() | Fig. 5.Polymerization shrinkage-strain of dual-cure resin cements investigated for different curing mode at 30 minutes. The values with the same superscript letter are not significantly different from each other based on multiple comparison Scheffe′test (P>.05). |
Table 1.
Dual-cure resin cements investigated in this study
Table 2.
Means and standard deviations in parenthesis of the polymerization shrinkage-strain of dual-cure resin cements investigated
Table 3.
Ratio of polymerization (%) at 10 minutes to 30 minutes