The effect of viscosity and activation mode on biaxial flexure strength and modulus of dual resin cements

Abstract

Purpose: The aim of this study was to evaluate the effects of curing mode and viscosity on the biaxial flexural strength (FS) and modulus (FM) of dual resin cements. Methods: Eight experimental groups were created (n=12) according to the dual-cured resin cements (Nexus 2/Kerr Corp. and Variolink II/IvoclarVivadent), curing modes (dual or selfcure), and viscosities (low and high). Forty-eight cement discs of each product (0.5 mm thick by 6.0 mm diameter) were fabricated. Half specimens were light-activated for 40 seconds and half were allowed to self-cure. After 10 days, the biaxial flexure test was performed using a universal testing machine (1.27 mm/min, Instron 5844). Data were statistically analyzed by three-way ANOVA and Tukey's test (5%). Results: Light-activation increased FS and FM of resin cements at both viscosities in comparison with self-curing mode. The high viscosity version of light-activated resin cements exhibited higher FS than low viscosity versions. The viscosity of resin and the type of cement did not influence the FM. Light-activation of dual-polymerizing resin cements provided higher FS and FM for both resin cements and viscosities. Conclusion: The use of different resin cements with different viscosities may change the biomechanical behavior of these luting materials.

Universal cements: dual activated and chemically activated

“…These results show the inefficiency of chemical activation, compared to dual activation, when seeking to attain the maximal conversion of monomers and consequently improve the bond strength of these cementing agents. [ 18 ] These findings were corroborated by the results in the present study, indicating that chemical activation without light activation of universal resin cements is not sufficient to attain an acceptable bond strength.…”

“…The DA universal cementing agents exhibited satisfactory results when compared with results in the literature. [ 18 ] In most of these systems, methacrylate monomers are partially substituted by phosphate monomers, such as MDP, which can promote chemical adhesion between the adhesive and the substrate. This appears to be a determining factor in the stability and durability of bonds.…”

Fracture Resistance of Lithıum Disilicate, Indirect Resin Composite and Zirconıa by Using Dual Cure Resin Cements

“…According to their study, all cements had an impact on the flexural strength on the ceramic, chemical cure cements had a superior flexural strength. Moreover, Fracncescantonio et al (31) evaluated the effects of curing mode and viscosity on the biaxial flexural strength (FS) and modulus (FM) of dual resin cements. Their study found that the use of different cements with different viscosities has an impact on the biomechanical behaviour of luting materials.…”