Effects of a bleaching agent on properties of commercial glass-ionomer cements

Abstract

ObjectivesThis study evaluated the effects of a bleaching agent on the composition, mechanical properties, and surface topography of 6 conventional glass-ionomer cements (GICs) and one resin-modified GIC.Materials and MethodsFor 3 days, the specimens were subjected to three 20-minute applications of a 37% H2O2-based bleaching agent and evaluated for water uptake (WTK), weight loss (WL), compressive strength (CS), and Knoop hardness number (KHN). Changes in surface topography and chemical element distribution were also analyzed by energy-dispersive X-ray spectroscopy and scanning electron microscopy. For statistical evaluation, the Kruskal-Wallis and Wilcoxon paired tests (α = 0.05) were used to evaluate WTK and WL. CS specimens were subjected to 2-way analysis of variance (ANOVA) and the Tukey post hoc test (α = 0.05), and KH was evaluated by one-way ANOVA, the Holm-Sidak post hoc test (α = 0.05), and the t-test for independent samples (α = 0.05).ResultsThe bleaching agent increased the WTK of Maxxion R, but did not affect the WL of any GICs. It had various effects on the CS, KHN, surface topography, and the chemical element distribution of the GICs.ConclusionsThe bleaching agent with 37% H2O2 affected the mechanical and surface properties of GICs. The extent of the changes seemed to be dependent on exposure time and cement composition.

The Effect of Home and In-Office Bleaching on Microhardness and Color of Different CAD/CAM Ceramic Materials

“…The effect of HP-based bleaching agents on the physical properties of various dental restorative materials has been widely assessed, including their effect on surface roughness, gloss, color, microhardness, and flexural strength. Tooth-colored restorative materials such as glass ionomers, resin-modified glass ionomers [ 5 ], and polyacid-modified composites [ 6 ] were shown to be negatively affected by bleaching procedures, while resin-composites showed variable results which were mainly material- and time-dependent [ 7 ]. Concerning ceramic materials, the effects of bleaching on surface roughness, color, and microhardness are not consistent among studies and appear to be dependent on the type of ceramic material, the method of surface treatment (whether autoglazed, overglazed, or polished), and the concentration and application time of the bleaching agent [ 7 ].…”

Comparative Evaluation of Two Glass Polyalkenoate Cements: An In Vivo Pilot Study Using a Sheep Model

“…However, the use of GPCs in orthopedic applications has been limited to the inner ear and for craniofacial implants [18,19]. Commercial GPCs (e.g., Fuji IX GP (GC Europe NV, Leuven, Belgium, and Ketac Cem Easymix (3M ESPE, St. Paul, MN, USA)) contain aluminum (Al) [20][21][22], which can have a deleterious effect on bone mineralization [23,24]. Therefore, attempts have been made to change the chemistry of GPCs and formulate a GPC without aluminum [14,25].…”

Eficácia Do Polimento Intra-Oral Na Rugosidade Superficial De Materiais Restauradores Diretos

“…Ao liberar flúor, os CIVs atuam no combate à cárie secundária (Bacchi;Bacchi;Anziliero, 2013), porém, esse material pode sofrer alterações superficiais consequente aos desafios no meio bucal, como mostrado no trabalho de Wongpraparatana et al ( 2017), onde o CIV sofreu aumento da rugosidade superficial após procedimento de clareamento dentário. Resultados obtidos por Camargo et al (2018) corroboram com estes achados, além de afirmar que o aumento da rugosidade superficial depende do tempo de exposição ao agente clareador e da composição do material restaurador.…”