Effects of a bleaching agent on properties of commercial glass-ionomer cements.
- Author:
Fernanda Lúcia Lago DE CAMARGO
1
;
Ailla Carla LANCELLOTTI
;
Adriano Fonseca DE LIMA
;
Vinícius Rangel GERALDO MARTINS
;
Luciano de Souza GONÇALVES
Author Information
- Publication Type:Original Article
- Keywords: Dental materials; Glass-ionomer cement; Tooth whitening agents
- MeSH: Compressive Strength; Dental Materials; Glass Ionomer Cements; Hardness; Microscopy, Electron, Scanning; Spectrum Analysis; Surface Properties; Tooth Bleaching Agents; Water; Weight Loss
- From:Restorative Dentistry & Endodontics 2018;43(3):e32-
- CountryRepublic of Korea
- Language:English
- Abstract: OBJECTIVES: This 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 METHODS: For 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 (a = 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 (a = 0.05), and the t-test for independent samples (a = 0.05). RESULTS: The 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. CONCLUSIONS: The 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.
