Fluoride Release Of Glass Ionomer Cements Research Articles

In vitro evaluation of some mechanical properties and fluoride release of glass-ionomer cement modified with seashell nanoparticles.

This research assessed the compressive strength and microhardness of glass-ionomer cement (GIC) after incorporating seashell nanoparticles and evaluated the inert fluoride-releasing ability. Seashell nanoparticles were synthesized by a mechanical grinding protocol. These particles were characterized by transmission electron microscopy and energy dispersive x-ray and added to the glass-ionomer powder in a weight-to-weight ratio. Seventy-five study samples were distributed into eight samples for each study group (control, 5%, and 10% seashell) to have 24 samples for each test of the study (compressive strength, microhardness, and fluoride release). One sample per group was prepared for the Fourier transform infrared spectroscopy (FTIR) test. The fluoride ion release was measured after one and four weeks of incubation period at 37 ºC, while other tests were conducted after 24 hours of incubation. In all the test variables, the 10% seashell group showed the highest significant mean, followed by the 5% seashell and the control group. However, there was no significant difference between the 5% and 10% seashell groups in the first week of fluoride release. According to the results, 10% seashell nanoparticles were the best to improve the mechanical properties of GIC and boost the fluoride-releasing potential.

Influence of Thermo-Light Curing on the Microhardness and Fluoride Release of Glass-Ionomer Cements

Influence of Thermo-Light Curing on the Microhardness and Fluoride Release of Glass-Ionomer Cements

Evaluating the Mechanical Properties, and Calcium and Fluoride Release of Glass-Ionomer Cement Modified with Chicken Eggshell Powder.

The aim of this study was to test the effect of adding chicken eggshell powder (CESP) to conventional glass-ionomer cement (GIC) on its mechanical properties, and fluoride and calcium release. CESP was added with proportions of 3% and 5% by weight to the powder component of conventional glass-ionomer cement. The specimens were categorized into group A: GIC without CESP; group B: GIC with 3% wt. CESP; and group C: GIC with 5% wt. CESP; there were 12 specimens in each group. Groups B and C showed higher compressive strength values compared to group A. However, microhardness scores were higher in group C compared to groups A and B. As for ion-release results, group B displayed the highest values of fluoride release followed by group C at both 7 and 30 days. Group C showed the highest amount of calcium release followed by both groups B and C at 7 days, while at 30 days, groups A and B showed higher calcium release compared to group C. The mechanical properties of conventional glass-ionomer restorative material were enhanced by the addition of CESP. Moreover, fluoride and calcium release were not compromised by adding CESP.

Characterization of Mechanical Properties, Fluoride Release and Colour Stability of Dental Sealants

Objective: To compare the mechanical properties, fluoride release, colour stability and spreading characteristics of glass ionomer cement (GIC), compomer (CO), chemical (CR) and light-cured resin based (LR) fissure sealants. Material and Methods: Cylinders were prepared to determine mechanical properties by diametral tensile strength tests (stored for 24h in distilled water at 37°C) and fluoride release (24 hours, 3, 7 and 15 days; deionised water). Disk shaped specimens were prepared to determine colour stability (1 week in pigmenting solution; 37°C; CIE L*a*b*; ΔE). A simplified method of a spreading test was proposed to predict viscosity characteristics of the tested materials. Data were analysed using one-way ANOVA followed by T-test (p<0.05). Results: Results showed differences between materials regarding all tested properties. CO was statistically more resistant than the other materials (p<0.05), but no difference was observed between CR and LR. The fluoride release of GICs was significantly higher than the other materials (p<0.05). CO showed lower ΔE than the other materials in the following order: CO<LR<GIC<CR. LR spread more than the other materials. Conclusion: All the materials developed to provide adequate preventive sealing tested in this study have particular physicochemical characteristics and should be recommended considering the particularities of each clinical case.

Antibacterial Activity and Fluoride Release of Glass-Ionomer Cement, Compomer and Zirconia Reinforced Glass-Ionomer Cement.

The cariostatic property of glass ionomer cement (GIC) stems from its ability to release fluoride into the oral environment. Recently, zirconia reinforced GIC has been launched which promises the protective benefits of glass ionomer while completely eliminating the hazard of mercury. To evaluate invitro antibacterial activity and fluoride release from two conventional glass ionomer cements (GC II and GC IX), compomer (Compoglass) and a zirconia reinforced glass ionomer cement (Zirconomer). The antibacterial activity of the cement specimens was evaluated against Streptococcus mutans using the agar inhibition test. Zone of inhibition on Mueller-Hinton agar plates was measured after 48 hours. The fluoride release from the cement specimens in ppm were measured at day 1, 7, 14 and 21 using a fluoride ion selective electrode. Data was analysed using one-way and two-way analysis of variance (ANOVA) followed by LSD post-hoc test. A p-value <0.05 was considered statistically significant. Statistically significant largest zone of inhibition was observed with Zirconomer. Also, significant differences were seen in fluoride release of different materials. At all the time intervals maximum fluoride release was observed with Zirconomer and minimum with Compoglass. This invitro investigation has revealed that zirconia reinforced GIC (Zirconomer) had maximum antibacterial activity against S.mutans and fluoride release.

Effect of Powder/Liquid Ratio on Fluoride Release of Glass Ionomers

Objective: Evidence shows that the powder/liquid mixing ratio recommended by the manufacturers is often not respected when mixing the glass ionomer (GI) powder and liquid, yielding a GI cement with disproportionate powder/liquid ratio. Considering the confirmed effect of powder/liquid ratio on the GI properties, and more importantly, its fluoride release potential, this study aimed to assess the effect of powder/liquid ratio on fluoride release of GI cements. Methods: Fuji II, Fuji II LC Improved and Fuji IX GI cements were used in this experimental study. Of each material, three groups with powder 20% less than recommended, the exact recommended ratio and powder 20% more than recommended, were prepared. To assess the fluoride release potential, 45 disc-shaped specimens measuring 2×4mm were prepared (5 per each group). After fabrication, the specimens were immersed in 5 mL of distilled water. The amount of fluoride released into distilled water was measured at days 1 to 7, and also at 13, 14, 15, 28, 29, 30, 58, 59, 60, 88, 89, and 90 days, using Ion Selective Electrode (ISE). After each time of measurement, distilled water was replaced. Data were analyzed using repeated measures ANOVA. Tukey’s post hoc test was used for pairwise comparison of groups and powder/liquid mixing ratio. For pairwise comparison of time points, the Bonferroni adjustment was applied (p<0.05). Results: Based on the results, although the amount of fluoride released from Fuji IX was higher than Fuji II, this difference was not statistically significant (p=0.589). The lowest fluoride release was seen in Fuji II LC and this difference was statistically significant (p<0.05). Change by 20% in the powder/liquid mixing ratio in the three GI cements had no significant effect on fluoride release (p=0.650, p=0.103, p=0.082). Conclusion: Fluoride release from GI was time-dependent and the amount of released fluoride decreased over time. Fuji II LC resin-modified GI (RMGI) released less fluoride than Fuji II and Fuji IX. Also, 20% change in powder/liquid mixing ratio had no significant effect on fluoride release

Therapeutic effect of glass‐ionomers: an overview of evidence

The requirements for an ideal restorative material include adhesion to tooth structure (enamel and dentine) and an ability to withstand the traumas of occlusion. However, some level of an anticaries effect is also desirable. After a long history of glass-ionomer cement (GIC) development, an evidence base in support of the therapeutic effect of GIC, particularly with regard to its anticaries effect, is emerging. This evidence is increasingly presented through systematic reviews of clinical GIC application and, to a certain extent, relates to a caries-preventive effect of the material itself. However, the strength of evidence supporting other aspects of GIC, such as a higher remineralizing effect, fluoride uptake in hard tooth tissue and fluoride release of GIC, is limited. Nevertheless, the results of these in situ and laboratory trials provide valuable insights into factors that facilitate understanding of the clinical efficacy of GIC.