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The aim of this study was to assess the microhardness of 5 glass ionomer cements (GIC) - Vidrion R (V, SS White), Fuji IX (F, GC Corp.), Magic Glass ART (MG, Vigodent), Maxxion R (MR, FGM) and ChemFlex (CF, Dentsply) - in the presence or absence of a surface protection treatment, and after different storage periods. For each GIC, 36 test specimens...
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Citations
... This was then succeeded by the placement of a microscopic glass slide. As a way to standardize the pressure used during the first setting of the material and to extrude any excess material, a weight weighing 200 grams was placed on top of the set, thereby pressing it against the top of the matrix and ensuring its retention [11]. The identical methodology was replicated for both the LC and ML groups, with the exception that no mixing occurred. ...
Objective. The objective of this study was to investigate the impact of storing two distinct types of glass ionomer cement (GIC) in a static magnetic field (SMF) on their mechanical characteristics, namely compressive strength, microhardness and degree of conversion. Methods. In the current investigation, 10 samples of each GIC type were utilized for each test. The entire tube of the resin modified type was preserved in a (SMF) for a duration of 48 hours, whereas just the powder of the conventional type was retained in SMF for the same time period. The SMF was calibrated to a value of 225 Gauss. Special identical molds were prepared for each test. All the tests were performed after 24 incubation period at 37 degrees in deionized water. The final data were analyzed using Wilcoxon Rank test (p ≤0.05). Results. The compressive strength of the conventional type and resin modified type that used in this study were significantly increased after exposed to the SMF from 195.33 (29.6) to 209.286 (11.78) 317.29 (55.4) to 523.38 (13.07) MPa respectively. The degree of conversion was also improved significantly after exposed to SMF, as the conventional type increased from 37.03 to 45.00, while the resin modified type from 42.2 to 59.3, the conventional type improved significantly for microhardness test but the resin modified type improved non-significantly. Conclusion. Storing the GIC in a 225 gauss SMF enhances the mechanical characteristics and the degree of conversion of resin modified and conventional GIC.
... Brinelll (37) are commonly used in measuring the microhardness value of restorative materials. Vickers test method was used in this study due to the availability of equipment and suitability for all materials and surfaces (38,39). In addition, surface hardness is related to the content and size of the restorative material (14,15). ...
... Although GIC is regularly used as a desirable restorative material in dentistry, they have disadvantages too, lack of sufficient strength, lack of toughness, technique-sensitive, poor wear resistant, resistance to fracture is poor, unaesthetic few shades, low bond strength and compressive strength (5) . ...
... However, HVGICs are still sensitive to water absorption and dehydration during early setting reactions [4,8,11,17]. For this reason, the application of a protective surface coating is recommended [4,10,18,19]. Previous studies have reported that applying a surface coating could improve their mechanical properties, including their surface hardness [20][21][22], but decrease their fluoride release and recharge abilities [23][24][25][26][27][28]. ...
The ability to release and recharge fluoride is a property of glass ionomer cement materials, which is an advantage for patients with a high caries risk. The purpose of this study was to evaluate the amount of released and recharged fluoride in recent uncoated high-viscosity glass ionomer cement (KetacTM Universal AplicapTM) with different surface coatings and at different time points. In total, 135 cylindrical-shaped specimens were equally divided into the following three groups: KetacTM Universal AplicapTM, KetacTM Molar AplicapTM, and KetacTM Fil Plus AplicapTM. The different coatings performed on each group were as follows: uncoated, coated with KetacTM Glaze, and coated with G-Coat PlusTM. The amounts of released and recharged fluoride were measured at 24 h and at weeks 1, 2, 3, and 4. The recharging agent was a 1.23% APF gel. KetacTM Universal AplicapTM showed the highest released fluoride at all time points and the highest recharged fluoride at weeks 1, 2, and 3. Both the KetacTM Glaze- and G-Coat PlusTM-coated specimens presented significantly lower released and recharged fluoride ions than the uncoated group at all time points (p < 0.001). Coating with G-Coat PlusTM significantly decreased the released and recharged fluoride compared to the coating with KetacTM Glaze at almost all time points (p < 0.05), except for weeks 1 and 2. The application of coating agents reduced the amount of released and recharged fluoride by the KetacTM Universal AplicapTM.
... Despite special properties of GICs, such as being self-adhesive to the tooth structure and fluoride-releasing potential, 24,25 poor mechanical properties have been shown in regular use of these restorative materials in dentistry. 26 Various modifications have been made in the cement powder and liquid of these materials. [27][28][29][30][31][32][33] Previous studies have shown that incorporating CNCs into the GIC improved the mechanical properties of the material. ...
Objective
Various modifications in formulation of glass ionomer cements (GICs) have been made in order to improve the clinical performance of these restorations. The aim of this work was to evaluate the microleakage and microshear bond strength (μSBS) of bacterial cellulose nanocrystal (BCNC)–modified glass ionomer cement (GIC) restorations in primary dentition.
Methods
A total number of 60 freshly extracted primary molar teeth were selected. Half of the samples were used for μSBS testing (in 2 groups, n = 15). In group 1, conventional GIC (CGIC) of Fuji IX (GC) was placed in cylindrical molds on dentinal surfaces. In group 2, CGIC of Fuji IX containing 1% wt of BCNCs was used. μSBS was evaluated using a universal testing machine. In another part of the study, microleakage of class V restorations was assessed according to the mentioned groups (n = 15). The sectioned samples were observed under stereomicroscope, and microleakage scores were recorded. SPSS version 16.0 (SPSS), independent samples t test, and Mann–Whitney U test were used for statistical analysis at a significance level of P < .05.
Results
Results showed statistically significant differences between the μSBS of CGIC and modified GIC groups (P < .0001). The BCNC-modified GIC group recorded significantly higher bond strength values (3.51 ± 0.033 vs 1.38 ± 0.034 MPa). Also, microleakage scores of CGIC and BCNC-modified GIC restorations were not significantly different (P = .57).
Conclusions
Based on our findings, it was concluded that incorporating BCNCs (1% wt) into the CGIC of Fuji IX significantly increased the μSBS to the dentin structure of the primary teeth.
... 9,10 The same thing was stated by Shintome et al, that the length of immersion in distilled water increased the value of GIC strength. 28 This strengthens the opinion that the compressive strength of GIC is regulated by the balance of water absorption from the beginning to the end of the gelation stage. 9,28 This explains the control subgroup which had higher compressive strength than the treatment sub-groups. ...
... 28 This strengthens the opinion that the compressive strength of GIC is regulated by the balance of water absorption from the beginning to the end of the gelation stage. 9,28 This explains the control subgroup which had higher compressive strength than the treatment sub-groups. ...
Glass ionomer cement as one of the restoration materials requires high compressive strength so it can last during functional activity. The latest glass ionomer cement comes with glass hybrid technology and a nanofilled resin-based protective coating which is said to increase the compressive strength of glass ionomer cement. The aim of this study was to analyze the effect of nanofilled resin-based coating and the types of glass ionomer cement materials on their compressive strength. Two types of commercial glass ionomer cement material were used; conventional (Fuji IX GP Extra), and hybrid (EQUIA Forte Fill) glass ionomer cement. Forty cylindrical (4 x 6 mm) samples were prepared in each group. The main group was divided into 4 subgroups (n=10) based on the protective coating used (EQUIA Forte Coat, Varnish, Control, Water + EQUIA Forte Coat). Eight subgroups were immersed in 37 °C distilled water for 7 days, then a compressive strength test was performed using a universal testing machine. The data analysis showed no significant difference in the compressive strength between the two types of glass ionomer cement materials (p>0.05). The use of a protective coating was associated with a significant decrease in the compressive strength (p<0.05). The use of glass ionomer cement without the application of a protective coating was considered to be quite good because the compressive strength value of the restoration still met the standards of the American Dental Association.
... The hardness of restorative material is critical for the clinical longevity of restorations [10]. Previous research has shown that microhardness determined by the Vickers method is a valid measure of the surface properties of GICs [11,12]. An increased roughness can be a predisposing factor for bacterial colonization [13]; when exceeds 0.2 µm, the caries risk is increased because of bacterial accumulation, plaque maturation, and acidity [14]. ...
Background: The aim of this study was to evaluate the effects of incorporation of hydroxyapatite (HA) derived from cuttlefish bone on the microhardness, surface roughness (SR), and fluoride
release (FR) of conventional cure, and resin-modified glass-ionomer cement. Methods: There were
four groups for each tested material; experimental glass-ionomer were made by addition and of 2, 5,
and 10 wt % HA respectively to conventional glass-ionomers Fuji II LC and Fuji IX GP Extra. One
group was prepared without the addition of HA particles. For SR and microhardness measurements
sectional Teflon molds (5 mm in diameter and 2 mm deep) were used to prepare 10 samples per group
(n = 80). The samples were stored in distilled water at 37 ◦C for 7 days prior to testing. The SR was
measured using a contact type profilometer and the microhardness was determined using a Vickers
micro-hardness tester at a load of 980 g for 15 s. For FR measurements, there were six samples per
group (n = 48), prepared in Teflon molds (8 mm in diameter and 2 mm deep). The FR was measured
with an ionoselective electrode in triplicates after 24 h, 7 days, and 45 days. Statistical analysis was
performed using one-way ANOVA with Tukey post-hoc test. Results and Conclusion: Microhardness
values obtained for Fuji II modified with 10 wt % HA were significantly higher compared to the other
two groups tested. Comparison of materials with respect to SR showed significant difference between
them (p < 0.0001) with Fuji II and Fuji IX modified with HA having higher SR values. Regarding FR,
Fuji IX showed statistically significant higher results than Fuji II, independently of HA modification,
and groups modified with 2 and 5 wt % HA showed significantly increased fluoride release in all
three time points.
... Brinell, Rockwell, Shore, Vickers and Knoop test methods can be used to measure the hardness of dental materials (Baloch et al., 2010). Although the Knoop's method is most commonly used method, due to availability of equipment, the Vickers test method was used in this study, which was also used in other relevant studies (Shintome et al., 2009;Bala et al., 2012). ...
The glass ionomer cements (GICs) is a generic name given to a group of materials widely used in clinical dentistry which if used after the specified expiration date, material properties may be affected. to evaluate the Vick ers microhardness, surface morphology and the energy dispersive X-ray microanalysis (EDX), of GICs with different expiration dates that were stored at room temperature. specimens of highly viscous glass ionomer cement (HVGIC) (Ketac Cem and Ketac Molar) and resin-modified glass ionomer cement (RMGIC) (Vitrebond) with different expiration dates (current, close to their expiration and expired) were prepared for Vickers microhardness test and scanning electronic microscopy (SEM) with EDX, measuring 5 mm in diameter and 2 mm length, per the manufacturer’s instructions, in standard cylindrical teflon molds. For the comparison of obtained values, the ANOVA test was used, while Tukey test was used for the multiple comparisons. In all the GICs used, the microhardness decreased as the expiration date approached, finding a significant statistical differen ce (P<0.05) in Ketac Molar and Vitrebond. SEM sample analysis revealed similar cohesive cracks in all tested materials. The EDX analysis revealed the presence of the elements F, Al and Si in all GICs and Ca only in Ketac Molar and Ketac Cem. The elements were found in a higher atomic percentage in the GICs with an current date and in a lower percentage in those with an expired date. HVGIC and RMGIC with an expiration date finish and that were stored at room temperature, suffer significant physical and chemical changes, which could put doubts its clinical effectiveness.
... During the testing intervals, the restorative biomaterial specimens (GICs) were stored in distilled water at 37°C. Shintome et al [26] observed that both surface protection and storage time in distilled water can increase the GIC microhardness values. ...
Background:
The development of dental caries is associated with various microorganisms and secondary caries formation is the main cause of restorations failure. The advice for restorative dental materials that have antimicrobial properties has stimulated the introduction of materials containing different antibacterial agents.
Objectives:
The present study has been designed to synthesize silver nanoparticles (AgNPs) and incorporate AgNPs and amoxicillin into glass ionomer cement (GIC) to synergize its effect on oral microbes. The effect of the added antimicrobial agents on compressive strength (CS) of GIC was also evaluated.
Material and methods:
Biosynthesis of AgNPs was done using Cupressus macrocarpa extract and AgNPs were characterized. A total of 120 disc-shaped specimens were prepared and classified into 4 main groups where Group A includes conventional GIC, Groups B and C include GIC with AgNPs or amoxicillin, respectively, while Group D included GIC with both AgNPs and amoxicillin. Each group was tested for the antimicrobial activity against both Streptococcus mutans (S. mutans) and Staphylococcus aureus (S. aureus). The distribution of biofilm was examined via a scanning electron microscope. The CS of the tested material was measured using a Material Test System.
Results:
The UV-visible spectrum showed a peak of 429 nm. Transmission electron microscopy, x-ray diffraction pattern and Fourier transform infrared analysis confirmed the formation of AgNPs with spherical to oblong polydispersed particles of diameter in the range of 13.5-25.8 nm. The maximum inhibitory zone was recorded for group D against both tested bacteria with a mean of 29 mm at first 24 h period to 15 mm at three weeks and showed antimicrobial rate 92.2% and 92.56%, against both strains, respectively. Additionally, group D disintegrated the structure of S. aureus biofilm and even kill bacteria in the biofilms. The addition of AgNPs and amoxicillin caused an insignificant effect on CS of GIC.
Conclusion:
TheAgNPs showed a synergistic effect in combination with amoxicillin and GIC dental restorative material against studied microorganisms. The agents can be safely added with minimal effect on the mechanical properties of the original cement.
... Hence, this has to be considered by professionals to have a safe and desirable material for all the clinical situation. 15 Scientist and researcher have introduced the products which have either avoided or reduced the major disadvantages of the material to the desirable levels. ...
Aims and objectives:
The aims and objectives of this study were to evaluate and compare the flexural strength and microhardness of zinc reinforced glass ionomer cement and glass ionomer type IX cement.
Materials and methods:
The sample size of twenty each of group I (zinc-reinforced glass ionomer cement) and group II (glass ionomer type IX cement) were selected. The samples were prepared in the customized steel molds and subjected to test for flexural strength and microhardness. The flexural strength was determined by the three-point bending test. After determining the flexural strength, the fragments were used to determine Vickers Hardness by means of an automatic microhardness indenter. The flexural strength and microhardness was calculated for all samples and subjected to statistical analysis. Two sample t-test with unequal variances were used, as the data are found to be from the same material. The normality was checked by using the usual normal probability plot. For flexural strength, p value was found to be 0.007530. Hence, zinc-reinforced glass ionomer cement was superior to glass ionomer type IX cement. For microhardness the p value was found to be 0.0023. So, glass ionomer type IX cement was superior to zinc reinforced glass ionomer cement.
Conclusion:
The zinc-reinforced glass ionomer cement showed enhanced flexural strength when compared to glass ionomer type IX cement, thus increasing the longevity whereas glass ionomer type IX cement had a better microhardness than zinc-reinforced glass ionomer cement. Hence, the mechanical properties of various materials should be considered for the long-term clinical success by selecting the appropriate material based on the clinical condition.
How to cite this article:
Patil K, Patel A, Kunte S, et al. Comparative Evaluation of the Mechanical Properties of Zinc-reinforced Glass Ionomer Cement and Glass Ionomer Type IX Cement: An In Vitro Study. Int J Clin Pediatr Dent 2020;13(4):381-389.
