Degree of Conversion and Hardness of Two Different Systems of the VitrebondTM Glass Ionomer Cement Light Cured with Blue LED

Abstract

This study investigated the physicochemical properties of the new formulation of the glass ionomer cements through hardness test and degree of conversion by infrared spectroscopy (FT-IR). Forty specimens (n = 40) were made in a metallic mold (4 mm diameter x 2 mm thickness) with two resin-modified glass ionomer cements, Vitrebond TM and Vitrebond TM Plus (3M/ ESPE). Each specimen was light cured with blue LED with power density of 500 mW/cm 2 during 30 s. Immediately after light curing, 24h, 48h and 7 days the hardness and degree of conversion was determined. The Vickers hardness was performed by the MMT-3 microhardness tester using load of 50 gm force for 30 seconds. For degree of conversion, the specimens were pulverized, pressed with KBr and analyzed with FT-IR (Nexus 470). The statistical analysis of the data by ANOVA showed that the Vitrebond TM and Vitrebond TM Plus were no difference significant between the same storage times (p > 0.05). Plus. The correlation between hardness and degree of conversion was no evidence in this study.

Monomer Conversion, Dimensional Stability, Biaxial Flexural Strength, Ion Release, and Cytotoxicity of Resin-Modified Glass Ionomer Cements Containing Methacrylate-Functionalized Polyacids and Spherical Pre-Reacted Glass Fillers

“…Additionally, the low viscosity of HEMA monomers may facilitate the mobility of reactive chains, which could increase the degree of monomer conversion [40]. The conversion of VB detected in the current study was higher than that reported in a previously published study (60-80%) [41]. This could be due to the effects of different light intensities from the curing unit.…”