Fluoride Release Ability 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.

Comparative Evaluation of Microhardness and Solubility of Different Combinations of Antibiotic Powders Added to Glass Ionomer Cement: An In Vitro Study.

The imbalance between remineralization and demineralization leads to the formation of secondary caries. Fluoride-releasing ability has been the characteristic property of glass ionomer cement (GIC), but it is uncertain if this property alone will be sufficient for the cessation of the growth of the organisms. Therefore, a restorative material with additional bacteriostatic properties needs to be introduced. To evaluate the microhardness and solubility of the conventional GIC after adding different combinations of antibiotic powders. In this study, the three groups were conventional GIC (group I), GIC + metronidazole + ciprofloxacin (group II), and GIC + metronidazole + amoxicillin/clavulanic acid (group III). The concentration of the double antibiotic combination was maintained at 1.5% w/w. The antibiotic powders were added to the GIC and evaluated for microhardness and solubility of the specimens. The mean microhardness level of group II was the highest, which was statistically significant using analysis of variance (ANOVA) with a p-value of 0.022. The comparison of each group's solubility in different solutions was not statistically significant. Along with the conventional properties of GIC, an additional therapeutic gain can also be obtained by incorporating various combinations of antibiotics, thereby arresting the progression of caries at the site of infection itself. This new approach shall help in community health programs, where treatment of a large population needs to be done within a short span of time and arrest the progression of caries activity in deep caries. Benson TL, Sogi S, Jain M, et al. Comparative Evaluation of Microhardness and Solubility of Different Combinations of Antibiotic Powders Added to Glass Ionomer Cement: An In Vitro Study. Int J Clin Pediatr Dent 2024;17(6):619-624.

Comparative Evaluation of the Fluoride Releasing Ability and Microbial Attachment of Glass-Hybrid Restorative Material

This study aimed to compare the fluoride-releasing ability and degree of microbial attachment of a newly developed glass-hybrid restorative material (GH) with those of a high-viscosity glass ionomer (HvGIC), resin-modified glass ionomer (RMGI), and composite resin (CR). In addition, the correlation between fluoride-releasing ability and microbial attachment between materials was evaluated. Specimens were prepared in a disc shape and divided into 4 groups according to the materials (GH, HvGIC, RMGI, and CR). The fluoride release experiments were performed in each group (n = 15). The amount of fluoride released was measured on days 1, 3, 7, 14, 28, and 42 after storage. For the microbial attachment experiment, 12 specimens were produced per group using <i>Mutans Streptococci</i> (<i>S.mutans</i> ), a cariogenic microorganism. <i>S. mutans</i> was cultured on the specimens for 24 hours, and the number of bacteria was measured. GH had the highest cumulative fluoride release and showed a significant difference when compared with RMGI (<i>p</i> = 0.001) and CR (<i>p</i> < 0.0001). Microbial attachment was the lowest in GH; however, no significant difference was observed between the materials (<i>p</i> = 0.169). There was no significant correlation between fluoride release from materials and microbial attachment (<i>p</i> > 0.05). From this perspective, remineralization of low-mineralized areas could be expected due to the high fluoride release of GH, and the effect of delaying the progression of dental caries could be predicted from the low cariogenic microbial attachment. Therefore, GH might be a useful restorative material for treating immature permanent teeth with hypomineralized enamel. However, further studies are needed about the degree of remineralization of hypomineralized areas after restoration and the capacity to recharge fluoride.

Fluoride Release and Rechargeability of Poly(lactic acid) Composites with Glass Ionomer Cement.

This study investigates the fluoride release, rechargeability and degradation behaviors of newly developed anticariogenic poly(lactic acid) (PLA) composites. The PLA composite with various concentrations (0%, 5%, 10%, 15% and 20% by weight) of glass ionomer cement (GIC) and sodium fluoride (NaF) were prepared using solvent casting method. The fluoride release, fluoride rechargeability and degradation behavior were evaluated. All experimental groups demonstrated fluoride-releasing ability. The highest level of fluoride ions released was found in PLA composite with sodium fluoride (PLA/NaF). Following the 28-day period, both groups showed a gradual reduction in fluoride ion released, ranging between 0.03 ± 0.01 and 0.53 ± 0.06 ppm, although remaining within the effective range for tooth remineralization. However, the rechargeability was only observed in PLA composite with GIC (PLA/GIC). Following an eight-week in vitro degradation test, all PLA/NaF groups displayed a significantly higher percentage of weight change and water absorption compared to the PLA/GIC and the control group. In SEM analysis, the formation of surface porosities was clearly noticed in all PLA/NaF. All specimens retained their structural integrity throughout the study. In conclusion, the newly developed PLA/GIC displays promising possibilities as an anticariogenic material. Furthermore, the rechargeability of these ions are repeatable, ensuring their long-term utility.

Comparative Evaluation of Fluoride Release from Four Commercially Available Pediatric Dental Restorative Materials.

The aim of this study was to evaluate the fluoride-releasing abilities of commercially available restorative materials such as-Activa™ BioActive-restorative™ material, Zirconomer (Shofu Inc), Beautifil® II (Shofu Inc), GC Gold Label 9 high strength posterior restorative glass ionomer cement (GIC Corp). A total of 40 disk specimens (10 of each material) were placed into distilled/deionized (DI) water and the fluoride release was measured for 30 days. Fluoride ion measurement was performed at the end of the 1st, 3rd, 7th, 15th, and 30th day under normal atmospheric conditions by fluoride ion selective electrode (F-ISE) (Orion 9609 BNWP, Ionplus SureFlow fluoride electrode, Thermo Scientific, United States of America) coupled to a benchtop analyzer (Hachsen Ion+). All the materials included in the study exhibited fluoride release. Although there were differences in the amounts of fluoride released between Activa™, Zirconomer, and GC Gold Label 9 the mean difference between these three groups was not found to be statistically significant. Beautifil® II showed low amounts of fluoride released at all time intervals. Among the above-compared materials Activa™ and Zirconomer exhibit both improved mechanical properties as well as they have fluoride-releasing ability so can be preferred over conventional glass ionomer restorations. Dhumal RS, Chauhan RS, Patil V, et al. Comparative Evaluation of Fluoride Release from Four Commercially Available Pediatric Dental Restorative Materials. Int J Clin Pediatr Dent 2023;16(S-1):S6-S12.

Evaluation of Fluoride Release in Chitosan-Modified Glass Ionomer Cements

ObjectiveThis study assessed the influence of chitosan nanoparticles on the fluoride-releasing ability of 4 glass ionomer cement (GIC) through an in vitro analysis. MethodsFour types of GIC (type II light cure universal restorative, type II universal restorative, GC Fuji VII, and type IX) were modified with nanochitosan particles; 10% chitosan was added to the glass ionomer liquid. Six specimens for each of the 4 groups were created, using expendable Teflon moulds. Discs of each type of GIC (n = 6) were immersed in deionised water at various time intervals. Electrodes selective for fluoride ions were employed to analyse the amount of released fluoride at 1, 7, 14, 21, and 28 days. ResultsChitosan-modified GICs showed greater fluoride release than conventional GICs at all time points. All samples showed an initial high release of fluoride that tapered off with time. The total amount of fluoride released increased from the 1st day to the 28th day on adding chitosan to all the 4 types of GIC. Amongst those, type IX high-strength posterior extra with chitosan released a considerably higher quantity of fluoride at all time intervals. ConclusionsIn all the experimental groups, adding chitosan to the glass ionomer liquid had an accelerating effect on its fluoride-releasing property.

Development of New Experimental Dental Enamel Resin Infiltrants-Synthesis and Characterization.

The aim of the present study was to obtain experimental infiltration materials, intended for the treatment of dental white spots, and to investigate them. Two series of infiltrants (P1–P6)/(P1F–P6F) were obtained, based on different monomer mixtures, without/with glass filler (with fluoride release ability). Each infiltrant from the second series contained the same amount of glass powder, and each infiltrant from the (P–PF) group contained the same resin composition. The characteristics of the experimental infiltrants were investigated by degree of conversion (DC), mechanical strength, water sorption (WS), and fluoride release, in addition to residual monomer for (P1F–P6F) infiltrants. The results were compared with those obtained for commercial Icon infiltrant. For the experimental infiltrants, without/with filler, the recorded DC was in the range of 58.27–89.70%/60.62–89.99%, compared with Icon (46.94%) 24 h after polymerization. The release of fluoride depends on the permeability of the polymer matrix, with respect to the water sorption, which may help to diffuse ions in the storage medium but which can also influence the release of residual monomers. The highest flexural strengths were recorded for the (TEGDMA/HEMA/Bis-GMA) infiltrants (133.94 ± 16.389 MPa/146.31 ± 7.032 MPa). The best experimental infiltrants were P2 and P2F (Bis-GMA/HEMA/TEGDMA).

An In Vitro Evaluation of the Mechanical Properties and Fluoride-releasing Ability of a New Self-cure Filling Material

The aim of this study was to examine and compare the flexural strength, shear bond strength, and fluoride-releasing ability of glass ionomer cement (GIC), Fuji IX GIC®, and a new alkasite filling material, Cention N®. The materials were divided into two groups, Fuji IX GIC® (n = 30) and Cention N® (n = 30) and further divided (n = 10) to test three parameters, the fluoride releasing ability, flexural strength, and shear bond strength. Fluoride release was checked using fluoride ion-selective electrode, and flexural strength and shear bond strength were tested using universal testing machine (Intron 3366, UK). Fluoride release of Fuji IX GIC® was significantly higher compared to that of control Cention N® over a period of 21 days. Flexural strength of Cention N® was significantly higher compared to Fuji IX GIC® and there were no significant differences in shear bond strength of both the materials. From the results of the study, it can be concluded that Cention N® is an alkasite filling material for the complete and permanent replacement of tooth structure in posterior teeth and can be a good alternative when compared to GICs on the basis of their superior mechanical properties. Cention N® is an innovative filling material for the complete and permanent replacement of tooth structure in posterior teeth and can be a good alternative when compared to GICs on the basis of their superior mechanical properties.

Effect of nano-hydroxyapatite incorporation on fluoride-releasing ability, penetration, and adaptation of a pit and fissure sealant.

Dental caries is one of the most common multifactorial oral diseases and can be prevented using pit and fissure sealants. To evaluate the effect of nano-hydroxyapatite (nanoHAP) incorporation on fluoride-releasing ability, penetration, and adaptation of a pit and fissure sealant. This was an in vitro study with two groups: conventional sealant and nanoHAP-incorporated sealant. Sealant penetration and adaptation were assessed using stereomicroscope and scanning electron microscope (SEM) (15 and 10 samples per group, respectively). Fluoride release was analyzed using ion-selective electrode (15 samples per group). The chi-square test was used to compare penetration and adaptation between the 2 groups, and an independent Student t test was used to compare fluoride release. The nanoHAP group showed significantly more samples with no bubbles (P=.001) and no debris (P<.001). SEM analysis showed a significantly greater percentage of adequate fissures in the test group (P=.007). The fluoride release was significantly higher in test samples with p values of .001 and .016 on day 1 and day 60, respectively. The incorporation of nanoHAP into the conventional pit and fissure sealant improved its penetration and adaptation properties along with fluoride release.

Study on the fluoride-releasing ability of dental GICmaterials in deionized water and artificial saliva environments

Study on the fluoride-releasing ability of dental GICmaterials in deionized water and artificial saliva environments

Effect of Fluoride Recharging on Fluoride Release and Surface Properties of Orthodontic Bracket Adhesives

The aim of this study was to compare fluoride release and surface changes according to different orthodontic bracket adhesives the application of fluoride products. We used non-fluoridated composite resin Transbond fluoridated composite resins Blugloo and LightBond, resin-modified glass ionomer Rely X™ Luting 2, and conventional glass ionomer Fuji I®. Fluoride release of five orthodontic bracket adhesives and fluoride release ability after application of three fluoride products (1.23% acidulated phosphate fluoride gel, Tooth Mousse Plus®, Fluor Protector, and a toothbrush with sodium fluoride-containing toothpaste) were measured using a fluoride electrode that was connected to an ion analyzer. After 4 weeks of fluoride application, the surface roughness and surface morphology were examined using a surface roughness tester and field emission scanning electron microscopy. The amounts of fluoride release were observed not only on application of Tooth Mousse Plus® and Fluor Protector on resin-modified glass ionomer Rely X™ Luting 2 and Fuji I®, but also during tooth brushing using fluoride-containing toothpaste. After application of Tooth Mousse Plus®, except Transbond XT, the surface roughness increased, and all orthodontic adhesives showed a partial drop of micro-particle filler. On application of 1.23% acidulated phosphate fluoride gel on all orthodontic bracket adhesives, their surface roughness increased. To bond the orthodontic bracket, resin-modified glass ionomer Rely X™ Luting 2 and Fuji I® adhesives are highly recommended if the amount of fluoride release is considered to confer a preventative effect on dental caries, and among the fluoride products, Tooth Mousse Plus® and Fluor Protector are better than 1.23% acidulated phosphate fluoride gel, and these are expected to prevent dental caries even during tooth brushing with fluoride-containing toothpaste.

Material properties on enamel and fissure of surface pre-reacted glass-ionomer filler-containing dental sealant

PurposeIn pediatric dentistry, sealants have been used to prevent caries. Due to its material properties such as fluoride-releasing ability and physical strength, surface pre-reacted glass (S-PRG) filler is added primarily to resin-based dental materials for clinical use. In this study, we investigated the properties of S-PRG filler containing sealant. MethodsBefore using sealant, the primer was applied to extracted bovine incisors. Scanning electron microscopy (SEM) observation revealed that the primer treatment caused no structural changes of enamel surface, unlike conventional phosphoric acid etching. Further, shear bond strength test was performed to measure the initial strength and durability after thermal cycling. Bond strength of S-PRG filler containing sealant was comparable to those of other sealants even though the former does not involve phosphoric acid etching. In addition, after treating the enamel surface with the primer or phosphoric acid, it showed excellent flowability in the primer group compared to phosphoric acid treatment. ResultsSEM observation showed that the sealant sealed the enamel surface as it migrated to reach the deep areas of the fissures. When the marginal sealing ability of the sealant was evaluated based on dye penetration, no dye penetration in the marginal region was observed in any specimens. In addition, measurement of the pH of an acid solution containing a cured specimen of the sealant containing S-PRG filler showed that the solution's pH became more alkaline as the immersion time increased. ConclusionThese findings suggest that the sealant is an extremely effective material for preventing caries.

Antibacterial potency and fluoride release of a glass ionomer restorative material containing different concentrations of natural and chemical products: An in-vitro comparative study.

BackgroundThis study investigated the antibacterial efficacy against Streptococcus mutans and fluoride release of a conventional glass ionomer (GI) contained natural and chemical agents.Material and MethodsTwo hundred and ten GI specimens were divided into ten groups (n=21) according to the concentrations of the additives as; Propolis extract containing GI (Groups 1, 2, 3) with concentrations of 0.25%, 0.75% and 1.25% respectively, Miswak extract containing GI (Groups 4, 5, 6) and Chlorhexidine containing GI (Groups 7, 8, 9) with the same concentrations. The prepared specimens were subjected to antimicrobial activity by well diffusion, bacterial adherence, and fluoride release (from 2 to 72 hours) assessments.ResultsA higher statistically significant antibacterial activity was found in (Groups 2, 3) compared to (Groups 8, 9), while (Groups 1, 4, 5, 6, 7, 10) no antibacterial efficacy was reported. For (Groups 2, 3) had a higher statistically significant anti-adherence effect compared to the other tested groups. Enhanced ascending increase in fluoride release was observed for (Groups 3, 4) compared to (GI).ConclusionsThe increased concentration of propolis extract had a synergistic effect on the antimicrobial activity of the tested GI. Additive concentrations of 0.25% Miswak and 1.25% propolis could enhance the fluoride-releasing ability of the tested GI. Key words:Propolis, miswak, chlorhexidine, glass ionomer, fluoride.

Effects of bonding materials on the mechanical properties of enamel around orthodontic brackets

To determine if the enamel around orthodontic brackets is significantly altered after demineralization followed by application of adhesives with and without fluoride-releasing ability. One hundred eight noncarious human premolars were divided into six groups of 18 each and exposed to a demineralization solution. Stainless steel brackets were bonded using two conventional composite resin etch-and-rinse systems, three self-etching primer (SEP) composite resin systems, and one resin-modified glass ionomer cement (RMGIC) system. One conventional and one SEP composite resin adhesive did not have fluoride-releasing ability, which was claimed for the other four adhesives. The elastic modulus and hardness of the enamel were determined with a nanoindenter at 10 equidistant depths ranging from 1-46 µm and at four regions: control (not exposed) enamel surface, under the adhesive, and at 50 µm and 100 µm from the bracket edges. Using the Kruskal-Wallis and Mann-Whitney U-tests (P < .0125 for statistical significance), these properties were compared at different regions. The same behavior was observed for values of elastic modulus and hardness. Significant differences were found within approximately 21 µm of the enamel surface for etching with 35% phosphoric acid or priming with SEP, but only minimal changes occurred for the SEP adhesive. Increases in near-surface elastic modulus and hardness of enamel were found with the SEP adhesive and RMGIC with fluoride-releasing ability. Clinical use of the fluoride-releasing adhesives investigated may prevent demineralization of enamel around brackets during orthodontic treatment.

Compressive strength, fluoride release and recharge of fluoride-releasing materials

The compressive strength, fluoride releases and recharge profiles of 15 commercial fluoride-releasing restorative materials have been studied. The materials include glass ionomers (Fuji IX, Ketac Molar, Ketac Silver, and Miracle Mix), resin-modified glass ionomers (Fuji II LC Improved, Photac-Fil, and Vitremer), compomers (Compoglass, Dyract AP, F2000, and Hytac) and composite resins (Ariston pHc, Solitaire, Surefil and Tetric Ceram). A negative linear correlation was found between the compressive strength and fluoride release ( r 2=0.7741), i.e., restorative materials with high fluoride release have lower mechanical properties. The fluoride-releasing ability can be partially regenerated or recharged by using a topical fluoride agent. In general, materials with higher initial fluoride release have higher recharge capability ( r 2=0.7088). Five equations have been used in curve fitting to describe the cumulative fluoride release from different materials. The equation [ F] c =[ F] I (1− e −bt)+β t best describes the cumulative fluoride release for most glass ionomers, resin-modified glass ionomers, and some high fluoride-releasing compomers and composites, whereas [F] c=[F] I/( t 1/2+ t)+ αt best describes the cumulative fluoride release for most compomers and composite resins. The clinic applications of different fluoride-releasing materials have also been discussed.

Relationship between the fluoride concentration of the fluoride-releasing elastomers and the acquired acid resistance of human enamel in vitro.

The objective of the study was to evaluate the relationship between the fluoride concentration of the fluoride-releasing elastomers and the acquired acid resistance of human enamel. Four kinds of fluoride concentration of the experimental fluoride-releasing elastomers were 1.25, 2.5, 3.75 and 5.0 wt%. An enamel block was cut into two smaller enamel blocks, one of which was set with an elastomer, the other as a control not set with elastomer. A plastic block that had the same shape as the small enamel block was also set with elastomer. Fluoride release and acid resistance tests were carried out. The mineral loss of the demineralized enamel was measured by microradiography. The results showed that the fluoride-releasing ability significantly increased with the increase of fluoride concentration in the elastomer (p < 0.05). The acid resistance of the enamel appeared to be enhanced greatly, however, its change was not proportional to the fluoride concentration in the elastomers.