Remineralization Potential of Three Restorative Glass Ionomer Cements: An In Vitro Study

Abstract

The aim of this in vitro study was to evaluate the remineralizing ability of three glass ionomers on demineralized dentin with different thicknesses and time periods. Fifty third molars were obtained and were sectioned into 1-, 2-, and 3-mm thick slices (n = 36 for each thickness). The specimens were demineralized with 18% EDTA for 2 h. From the glass ionomer cements (GICs) under study (Ketac Molar Aplicap, Equia Forte, or Riva Light Cure), 1 mm was placed over each slice, set, and preserved in PBS until observation after 1, 7, 14, and 28 days after placement. For each material, thickness, and time, three samples were prepared. Using Fourier Transform Infrared Spectrometry (FTIR), apatite formation was determined on the side opposite to that on which the material had been placed. By means of Energy Dispersive Spectroscopy (EDX), the changes in the Calcium/Phosphate (Ca/P) ratio were evaluated. These changes were compared between the different materials by means of a two-way ANOVA test, considering time and dentin thickness, for a significance level of p < 0.05. Results: FTIR showed a peak at 1420 cm−1, evidencing the presence of carbonated hydroxyapatite in all the materials after 14 days, which indicates that a remineralization process occurred. Riva Light Cure showed the most homogeneous results at all depths at 28 days. The Ca/P ratio was maximum at 7 days in 2 mm of dentin for Riva Light Cure and Equia Forte HT (3.16 and 3.07; respectively) and for Ketac Molar at 14 days in 1 mm (3.67). All materials induced remineralization. Equia Forte achieved the greatest effect at 2 mm and Ketac Molar at 1 mm, whereas Riva Light Cure showed similar results at all depths. In terms of Ca/P ratio, Equia Forte and Riva Light Cure remineralized best at 2 mm, whereas for Ketac Molar, it was 1 mm. Carbonate apatite formation was higher at 24 h and 7 days for Ketac Molar, whereas it decreased at 14 days for Ketac Molar and peaked in Riva Light Cure and Equia Forte.

Evaluation of setting kinetics, mechanical strength, ion release, and cytotoxicity of high-strength glass ionomer cement contained elastomeric micelles

“…The release of multiple elements was expected to enhance the bioactive properties of GICs, such as promoting mineralization or providing buffering effects [ 11 , 63 ]. For example, the replacement of Ca with Sr in glass ionomer cement showed an increase in the radiopacity of the material and enhanced tooth remineralization [ 64 , 65 ]. Sr was also believed to exhibit synergistic effects with fluoride in controlling dental biofilm [ 66 ].…”

Remineralizing Ability of Resin Modified Glass Ionomers (RMGICs): A Systematic Review

“…There are several articles that support the use of EDX to assess the remineralizing effect of GICs in association with FTIR [ 49 , 50 , 51 ], Micro-Raman [ 52 ], and XRD [ 53 , 54 , 55 ]. These techniques are less invasive and allow the analysis of the same sample at further endpoints as they do not require a coating.…”

Fluoride exchange by glass-ionomer dental cements and its clinical effects: a review

“…The amount of fluoride needed to affect S. mutans populations in the mouth has been determined. Survival rates dropped dramatically at concentrations of 500 mmol dm −3 [ 108 ] and levels as low as 10 mmol dm −3 were sufficient to inhibit metabolism and render the bacteria unable to metabolize carbohydrate [ 69 , 109 ]. These values are equivalent to approximately 10,000 and 200 ppm, respectively.…”