Microshear Bond Strength of Nanoparticle-Incorporated Conventional and Resin-Modified Glass Ionomer to Caries-Affected Dentin.

Zahra Fattah,Zahra Jowkar,Safoora Rezaeian,Lucas Da Fonseca Roberti Garcia

doi:10.1155/2021/5565556

Abstract

The purpose of this study was to assess the influence of three different types of nanoparticles (silver (SNPs), titanium dioxide (TNPs), and zinc oxide (ZNPs)) on the microshear bond strength of conventional glass ionomer cement (CGIC) and resin-modified glass ionomer cement based on whether CGIC or RMGIC is used with four subgroups (based on the incorporation of SNPs, ZNPs, and TNPs in addition to a control subgroup) (n = 12) as follows: CGIC, CGIC + TNP, CGIC + ZNP, CGIC + SNP, RMGIC, RMGIC + TNP, RMGIC + ZNP, and RMGIC + SNP. After 24 hours, the μSBS of specimens was tested and the obtained data were analyzed using two-way ANOVA and Tukey's HSD test. The obtained results showed that the incorporation of TNPs in two glass ionomers was not statistically significant compared with the control subgroups (p > 0.05). In the first group, the highest and lowest mean μSBS were, respectively, observed in the CGIC + SNP subgroup and CGIC + ZNP subgroup. In the second group, RMGIC + ZNP and RMGIC + SNP, respectively, showed the highest and lowest mean μSBS compared to the other subgroups. According to the results, it can be concluded that TNPs can be incorporated into both CGIC and RMGIC without compromising the bond strength of glass ionomers. SNPs and ZNPs can be, respectively, added to CGICs and RMGICs to improve the bond strength of the restoration.

Highlights

Modern restorative dentistry is mainly focused on preserving tooth structure during cavity preparation and applying nonaggressive methods in treating carious lesions [1]
To the best of the authors’ knowledge, there is no previous study investigating the effect of incorporating metal NPs into glass ionomer cements on the bond strengths of a conventional glass ionomer cement (CGIC) and a resin-modified glass ionomer cement (RMGIC) to caries-affected dentin (CAD). e null hypothesis of this paper was that incorporating three types of NPs (SNP, Titanium dioxide NP (TNP), and Zinc oxide NP (ZNP)) into a CGIC and a RMGIC had no effect on their microshear bond strengths to CAD
Among the subgroups of group 1, the highest mean μSBS was observed in subgroup 4 (CGIC + Silver NP (SNP)) (p < 0.001), while subgroup 3 (CGIC + ZNP) had a statistically significantly lower mean μSBS than the other subgroups (p < 0.001)

Summary

Introduction

Modern restorative dentistry is mainly focused on preserving tooth structure during cavity preparation and applying nonaggressive methods in treating carious lesions [1]. The mechanical properties of nanoparticle-incorporated restorative materials should be studied before applying them in CAD treatment. To the best of the authors’ knowledge, there is no previous study investigating the effect of incorporating metal NPs into glass ionomer cements on the bond strengths of a conventional glass ionomer cement (CGIC) and a resin-modified glass ionomer cement (RMGIC) to CAD. E null hypothesis of this paper was that incorporating three types of NPs (SNP, TNP, and ZNP) into a CGIC and a RMGIC had no effect on their microshear bond strengths to CAD. In order to avoid bias in data collection, blinding was considered during testing the specimens After that, they were placed in a jig attached to a universal testing machine (Instron, Z020, ZwickRoell, Germany) to measure their microshear bond strengths (μSBS). Exposing flat midcoronal dentin surfaces with CAD and mounting the specimens in acrylic resin

Restorative procedures

Findings

Discussion

Conclusions