Mechanical and dentin bond strength properties of the nanosilver enriched glass ionomer cement.

Z Jowkar,M Jowkar,F Shafiei

doi:10.4317/jced.55522

Abstract

BackgroundThe aim of this study was to investigate the mechanical properties and dentin microshear bond strength of a conventional glass ionomer cement (GIC) compared to GIC supplemented with silver nanoparticles (SNPs) at 0.1% and 0.2% (w/w).Material and MethodsSNPs were incorporated into a conventional GIC at 0.1% and 0.2% (w/w). The unmodified GIC was used as the control group. Compressive strength, flexural strength, and micro-shear bond strength (µSBS) to dentin were evaluated using a universal testing machine. Surface microhardness was determined using a Vickers microhardness tester. The data were analyzed using one-way analysis of variance (ANOVA) and Tukey’s test.ResultsGICs containing 0.1% and 0.2% (w/w) SNPs significantly improved compressive strength, surface microhardness, and dentin µSBS compared to the unmodified GIC (p<0.05). A significant increase in the flexural strength was found for the GIC containing 0.2% (w/w) SNPs (p<0.05). However, the GIC containing 0.1% (w/w) SNPs did not affect flexural strength.ConclusionsGIC supplemented with SNP is a promising material for restoration because of its improved mechanical and bond strength properties. Therefore, it may be suggested for use especially in higher stress-bearing site restorations. Key words:Glass ionomer cement, mechanical properties, micro-shear bond strength, silver nanoparticle.

Highlights

Glass-ionomer cements (GICs) are widely accepted as dental restorative materials because of their unique properties such as chemical adhesion to dental tissues, fluoride releasing, low thermal expansion coefficient, and good biocompatibility [1]
A piece of micro-tube from a micro-bore tygon tubing (R-3603, Norton Performance Plastic, Cleveland, OH) with the internal diameter of 0.7 mm and approximate height of 0.5 mm was placed on the bonding surface defined by an adhesive tape with a punched hole over the center of the flattened dentin surface and subsequently filled with GIC, GIC incorporated with 0.1% silver nanoparticles (SNPs), and GIC incorporated with 0.2% SNPs (n=10 for each group)
Was a significant increase in the compressive strength of GIC+0.2 % (w/w) SNP group compared to GIC+0.1 % (w/w) SNP group (P < 0.05). -Micro-shear bond strength to dentin Micro-shear bond strength to dentin increased significantly with increasing the concentrations of SNP into GIC compared with the control group (P < 0.05) (Table 1)

Summary

Introduction

Glass-ionomer cements (GICs) are widely accepted as dental restorative materials because of their unique properties such as chemical adhesion to dental tissues, fluoride releasing, low thermal expansion coefficient, and good biocompatibility [1]. It has been reported that the incorporation of titanium dioxide nanoparticles into restorative GIC significantly improved antibacterial activity and physical properties such as flexural strength, compressive strength, and Vickers microhardness without compromising the bond strength of GIC to enamel and dentin [1]. GIC incorporated with titanium dioxide nanoparticles demonstrated acceptable to moderate biocompatibility in culture with human normal oral cells and human cancer cells [12] Another nanoparticle which has been investigated in dentistry mainly because of its sustained ion release and the resultant long-term antibacterial property is silver nanoparticle (SNP). The aim of this study was to investigate the mechanical properties and dentin microshear bond strength of a conventional glass ionomer cement (GIC) compared to GIC supplemented with silver nanoparticles (SNPs) at 0.1% and 0.2% (w/w). It may be suggested for use especially in higher stress-bearing site restorations

Objectives

Methods

Results