Fluoride-releasing Restorative Materials Research Articles

Fluoride and caries prevention: a scoping review of public health policies.

Dental caries is the most common infectious disease, affecting approximately 60 to 90% of the world population, especially young children, and disadvantaged communities. Due to the extremely high prevalence and the significant negative impact on general health, well-being, and quality of life it is considered a global public health problem. Despite the improvement of policies to promote oral health care in the past decades, dental caries is still a healthcare challenge, characterized by increasing disparities among different social groups between and within countries. Fluoride-based prevention of dental caries is a cost-effective approach, that has been implemented since 1940's. It includes systemic and topical administrations, through community-based or individual programs. Preventive interventions should be tailored to individual and community caries risk assessment and estimate of cumulative fluoride intake, in order to maximize the preventive effect and avoid the risk of potential adverse effects associated with excessive fluoride exposure. Regulation of public health policies plays a major role in this context. Scoping review. The aim of this scoping review was to report an overview of current guidelines regarding fluoride-based preventive strategies for dental caries and relevant policies on the matter, as well as to address current issues related to public health aspects of dental caries prevention. We searched for the relevant literature on the matter, focusing on policy documents, such as recommendations, position papers and guidelines, issued from the major scientific and regulatory institutions involved in oral health promotion and on publications concerning relevant aspects of public health law. Prevention of dental caries through fluoride can rely on topical fluorides for home-use (toothpastes and mouthrinses), professionally applied topical fluorides (gels, varnishes, silver diamine fluoride, fluoride-releasing restorative materials and sealants), fluoride supplements (tablets and drops), and community-based strategies (community water fluoridation, fluoridated salt and milk). Current relevant guidelines for all these preventive aids are outlined in the paper. A significantly greater preventive effect of topical fluorides has been widely established in the recent past, as compared to systemic effects. Furthermore, increasing concerns have emerged on potential adverse effects on general health associated with early and excessive systemic exposure to fluoride, especially for children, supported by recent meta-analyses. Also, community water fluoridation has raised significant aspects of relevance for health law and policies. In a public health perspective, healthcare policymakers should tackle social iniquities by promoting information and oral health literacy, through community and school-based programs, ensuring access to early dental visits and basic dental care and improving availability and affordability of fluoride topical products. Conclusions. Fluoride-based prevention can provide a simple and cost-effective approach to reduce the incidence of dental caries and the associated social burden. Among fluoride-based preventive strategies, systemic community-based administration of fluoride should be considered with great caution, due to the unfavorable risk-benefit ratio currently established. Topical fluoridated pro-ducts are generally preferred, given the optimal risk-benefit ratio. Further efforts must be made to identify and tackle the barriers to dental caries prevention and related social iniquities from a public health perspective. Policies and laws on oral health should promote access to caries prevention with targeted comprehensive strategies.

The F word revisited

Dental UpdateVol. 50, No. 6 CommentThe F word revisitedFJ Trevor BurkeFJ Trevor BurkeSearch for more papers by this authorFJ Trevor BurkePublished Online:13 Jun 2023https://doi.org/10.12968/denu.2023.50.6.473AboutSectionsView articleView Full TextPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail View article References National Institute of Dental and Craniofacial Research. The story of fluoridation. Available at: https://tinyurl.com/uw36c6v5 (accessed May 2023). Google ScholarRandall RC, Wilson NH. Glass-ionomer restoratives: a systematic review of a secondary caries treatment effect. J Dent Res 1999; 78: 628–637. https://doi.org/10.1177/00220345990780020101 Medline, Google ScholarWiegand A, Buchalla W, Attin T. Review on fluoride-releasing restorative materials – fluoride release and uptake characteristics, antibacterial activity and influence on caries formation. Dent Mater 2007; 23: 343–362. https://doi.org/10.1016/j.dental.2006.01.022 Medline, Google ScholarYengopal V, Mickenautsch S, Bezerra AC, Leal SC. Caries-preventive effect of glass ionomer and resin-based fissure sealants on permanent teeth: a meta analysis. J Oral Sci 2009; 51: 373–382. https://doi.org/10.2334/josnusd.51.373 Medline, Google Scholar FiguresReferencesRelatedDetails 2 June 2023Volume 50Issue 6ISSN (print): 0305-5000ISSN (online): 2515-589X Metrics History Published online 13 June 2023 Published in print 2 June 2023 Information© MA Dentistry Media LimitedPDF download

Influence of fluoride-releasing materials in the inhibition of enamel and dentin demineralization around restoration

Objective: The aim was to evaluate the influence of fluoride-releasing restorative materials in enamel and dentinmicrohardness. Material and Methods: 40 blocks (5x5x3 mm) from cervical third of human molars received a cavitypreparation between the enamel and dentin, and the restorations were subjected to in vitro caries model. Specimenswere randomly restored with (n=10): conventional glass ionomer cement (Ketac Cem, 3M ESPE); polyacid-modifiedcomposite resin (Ionoseal, VOCO); resin-modified glass ionomer cement (Ionofast, Biodinâmica); or microhybridcomposite resin (Filtek Z250, 3M ESPE). The specimens were sectioned longitudinally and enamel and dentinKnoop microhardness were determined at different distances from the restorative material (100, 200 and 300 um)and depth of surface (20, 40 and 60 um). The data were submitted to three-way repeated measures ANOVA andTukey´s test (a=0.05). Results: For enamel, the double interactions between material x distance and material xdepth were statistically significant. In all depths and distances, the highest values of enamel microhardness wereobserved for Ketac Cem. In dentin, the materials differed statistically from each other, and Ionoseal obtained highermicrohardness values than those found in Ionofast. Conclusion: Conventional glass ionomer cement is more effectivein preventing enamel demineralization around restoration followed by the polyacid-modified composite resin. Indentin, the polyacid-modified composite resin obtained better performance than resin-modified glass ionomer cement.KEYWORDSCompomers; Dental caries; Glass ionomer cements; Hardness tests; Composite Resins.

Effect of Fluoride Recharge on the Microleakage of Fluoride-Releasing Restorative Materials: An Ex Vivo Confocal Laser Scanning Microscopy Study.

ABSTRACTContext:Success or failure of a restoration depends on its ability to bond to the tooth structure, to reduce microleakage, and to inhibit secondary caries. Fluoride-releasing materials have the inherent potential to release fluoride and are also capable of recharging themselves with topical agents.Aim:The aim of this study was to compare and evaluate the effect of fluoride recharge on microleakage of different restorative materials.Materials and Methods:Eighty extracted teeth were collected and split mesiodistally into 160 specimens. Class V cavities were prepared on buccal and lingual surfaces. Specimens were divided into four groups of 40 each based on the restorative material. Group I: Glass ionomer; Group II: Resin composite; Group III: Giomer; and Group IV: Alkasite. The restored teeth were stored in artificial saliva. Each group was divided into four subgroups for fluoride recharge and subsequent confocal laser scanning microscopy (CLSM) examination: (A) no fluoride recharge and CLSM examination after 24 h, (B) no fluoride recharge and CLSM examination after 3 weeks, (C) fluoride recharge once at third week followed by CLSM examination at 6 weeks, and (D) fluoride recharge twice at third week and sixth week followed by CLSM examination at 9 weeks.Statistical Analysis:Kruskal−Wallis and Mann−Whitney U tests were performed to analyze the obtained data.Results:A significant difference in microleakage was noted among resin composite and other groups except Cention-N, whereas no significant difference was noted pre- and post-fluoride recharge.Conclusion:Increased microleakage was noted post-fluoride recharge, although statistically not significant.

AFM and SEM/EDS characterization of surfaces of fluorine-releasing bulk-fill restorative materials aged in common liquids

This study investigated the surface roughness (SR), surface microhardness (SH), and chemical composition of recently developed fluoride-releasing restorative materials aged in common liquids. A total of 276 disc-shaped samples with a diameter of 8 mm and a height of 2 mm were prepared by using four restorative materials: alkasite, Activa, Equia Forte, and Zirconomer. Atomic force microscopy (AFM) and the Vickers microhardness test were used to measure SR and SH, respectively. Scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM/EDS) was used for elemental analysis of the materials. The prepared samples were divided into 3 subgroups and immersed in coffee, cola, and saliva for 1 week at 37°C and 100% humidity. Cola and coffee significantly increased the SR of all materials except Zirconomer immersed in coffee (P < 0.05). The microhardness of alkasite and Activa significantly decreased in all liquids (P < 0.05) The percentage of fluorine (F) in the materials significantly changed after immersion for some liquids (P < 0.05). Aging differentially affected the surface characteristics and elemental mass ratios of the studied materials.

Enamel Demineralization Resistance and Remineralization by Various Fluoride-Releasing Dental Restorative Materials.

The aim of this study is to investigate the resistance of various fluoride-releasing restorative materials against the demineralization and remineralization of enamel surfaces, including those that have been recently introduced to the market. Three different fluoride-releasing restorative materials were considered: glass ionomer (FI), resin-modified glass ionomer (RL), and an alkasite restorative material (CN). The acid neutralization ability was investigated using pH measurement, and the concentrations of released fluoride and calcium ions were measured. Finally, the demineralization resistance and remineralization effects of enamel were observed using a microhardness tester and SEM. CN showed an initial substantial increase in pH followed by a steady increase, with values higher than those of the other groups (p < 0.05). All three groups released fluoride ions, and the CN group released more calcium ions than the other groups (p < 0.05). In the acid resistance test, from the microhardness and SEM images, the CN group showed effective resistance to demineralization. In the remineralization test, the microhardness results showed that the FI and CN groups recovered the microhardness from the values of the demineralized enamel surface (p < 0.05). This was confirmed by the SEM images from remineralization tests; the CN group showed a recovered demineralized surface when immersed in artificial saliva for 7 days. In conclusion, alkasite restorative material can be an effective material when used in cariogenic environments.

The Comparison of Biofilm Formation, Mechanical and Chemical Properties between Glass Ionomer Cement and Giomer

Aims: The aim of this study was to compare compressive strength and its correlation with the surface morphology and chemical elements of GIC and Giomer, as well as to determine the fluoride amount effect on the bacterial biofilm formation of GIC and Giomer. Background: The liability of Glass Ionomer Cement (GIC) mechanical properties is overcome with better antibacterial properties among restorative materials. Another fluoride-releasing restorative material, such as Giomer, has been discovered and is expected to overcome the issues with GIC’s mechanical properties; however, no research has been conducted related to antibacterial properties in Giomer. Objective: To compare compressive strength and its correlation with the surface morphology and chemical elements, then determine the fluoride amount effect on the bacterial biofilm formation of GIC and Giomer. Methods: Sixteen specimens of GIC and Giomer were prepared for a compressive strength measurement with the Universal Testing Machine. Sixteen specimens of GIC and Giomer were incubated for three days with the Streptococcus mutans culture at 37°C. The bacterial colonization was calculated using the Colony Forming Unit (CFU) and bacterial adhesion was calculated using a Scanning Electron Microscope (SEM). The mechanical properties’ compressive strength measurement, surface morphology, and chemical elements analyses were performed using SEM-EDX. Results: The compressive strength of Giomer was higher than GIC (P=0.001). The higher compressive strength of Giomer was reflected by a predominant regular surface, fewer voids, smaller and denser particles, and a higher content of silica and carbon. The bacterial biofilm on the surface of Giomer was higher than GIC, although there was no significant difference. GIC and Giomer have identical chemical elements: C, O, F, Na, Al, Si, P, and Ca. Conclusion: The compressive strength of Giomer is better than GIC; however, the biofilm formation of Giomer is higher than GIC, whereas GIC has a higher fluoride content but inferior in surfaces morphology characteristic

Effects of surface coating on the flexural strength of fluoridereleasing restorative materials after water aging for one year.

To evaluate the effects of surface coating and one-year water storage on the flexural strength of fluoride-releasing restorative materials. Forty specimens were prepared from each material; GCP Glass Fill (GCP), Amalgomer CR (AHL), Zirconomer (Shofu), Fuji IX GP Capsule (GC), Beautifil II (Shofu), Estelite Σ Quick (Tokuyama) and reliaFIL LC (AHL). The specimens were randomly divided into two groups; surface coated with G-Coat Plus (GC) and uncoated. Each group was subdivided into two groups stored in distilled water at 37◦C for 24 h and 1 year before testing (n=10). The flexural strength was evaluated using three-point bending test according to the ISO 4049:2009 standard using a universal testing machine. After flexural strength test, a cross-section of the coated specimens was evaluated with scanning electron microscopy (SEM). A significant increase was observed on the flexural strength of Amalgomer CR, Zirconomer and Fuji IX GP after 24 h when G-Coat Plus was applied (p<0.05). This significant increase was observed on the flexural strength of only Amalgomer CR and Zirconomer after 1 year (p<0.05). The highest flexural strength was obtained with Beautifil II, Estelite Σ Quick and reliaFIL LC after 24 h and 1 year (p<0.05). After 1 year, there was decrease on the flexural strength of the other materials except Beautifil II, Estelite Σ Quick and reliaFIL LC. The resin coating improved the flexural strength of some glass ionomer-based materials but the water aging decreased the same physical properties.

Commercially Available Fluoride-Releasing Restorative Materials: A Review and a Proposal for Classification.

Resin composite and glass ionomer cement (GIC) are the most commonly used dental materials to perform direct restorations. Both have specific characteristics that explain their popularity and their limits. More than 20 years ago, the first attempt (followed by others) to combine the advantages of these two families was performed with compomers, but it was not very successful. Recently, new formulations (also called ‘smart materials’) with claimed ion release properties have been proposed under different family names, but there are few studies on them and explanations of their chemistries. This comprehensive review aims to gather the compositions; the setting reactions; the mechanical, self-adhesive, and potential bulk-fill properties; and the ion release abilities of the large existing families of fluoride-releasing restorative materials and the new restorative materials to precisely describe their characteristics, their eventual bioactivities, and classify them for an improved understanding of these materials. Based on this work, the whole GIC family, including resin-modified and highly viscous formulations, was found to be bioactive. Cention N (Ivoclar Vivadent, AG, Schaan, Lietschentein) is the first commercially available bioactive resin composite.

In Vitro Inhibition of Enamel Demineralisation by Fluoride-releasing Restorative Materials and Dental Adhesives.

To determine the ability of 5 contemporary fluoride-releasing restoratives and 3 fluoride-releasing adhesives to inhibit enamel demineralisation surrounding restorations, and the associations between inhibition and the levels of fluoride released from these materials. Five fluoride-releasing restoratives (Fuji IX GP, Ketac N100, Dyract Extra, Beautifil II and Wave) and 3 fluoride-releasing adhesives (Stae, Prime & Bond NT and Fluoro Bond II) were investigated. Eight disks of each material were prepared. Fluoride release was measured daily using a fluoride-ion-selective electrode for 15 days. Twenty-four cavities for each group were restored with a restorative and an adhesive. Specimens were subjected to thermal stress and stored for 30 days in saline solution. After a 15-day pH-cycling regimen, two 150-μm-thick sections were derived from each specimen. Enamel lesion depth was measured at 0, 100, and 200 μm from each restoration's margin via polarised light microscopy. Of the restoratives investigated, Fuji IX GP released the most fluoride. The fluoride-releasing restoratives tested exhibited shallower enamel lesions than did the control group at all distances tested (p < 0.05). Fuji IX GP yielded significantly lower enamel lesion depth than did the other experimental materials. The depths of enamel lesions did not differ significantly when comparing restoratives applied with a fluoride-releasing adhesive with those applied with a non-fluoride-releasing adhesive. The fluoride-releasing materials tested reduced enamel demineralisation but to different extents, depending on their levels of fluoride release. Fluoride-releasing adhesives did not influence enamel lesion formation.

Fluoride releasing restorative materials: a review

Fluoride compounds are incorporated as anticariogenic agents in numerous restorative materials. Incorporation of fluoride into restorative materials impart anticariogenic character by various mechanisms including reduction of demineralisation, enhancement of remineralisation, interference of pellicle and plaque and inhibition of microbial growth and metabolism. In addition, the application of the topical fluoride in the form of toothpaste and varnish is also considered as the most effective method of caries prevention. The fluoride combines with HA of the tooth and forms an acid-resistant fluorapatite (FAP) crystals. Also, fluoride enters into the cells of the bacteria and inhibits carbohydrate metabolism, which eventually kills the bacteria. The objective of this review was to emphasise the fluoride-releasing restorative materials available in dentistry.

Comparative evaluation of fluoride release and re-release and recharge potential of Zirconomer Improved and Cention.

Background:The cariostatic action associated with fluoride-releasing restorative materials is mainly attributed to a sustained release of fluoride. This research aims on comparing Cention N and Zirconomer Improved in vitro fluoride release and re-release.Methods:Test materials were grouped into two categories containing 15 samples each. The cumulative fluoride release and re-release measurements was made during 1st, 7th and 15th day. The independent sample t-test and paired t-test was used to check mean differences. The level of significance was kept at p<0.05.Results:At day 1, 7 and 15 the initial fluoride release of zirconomer group was significantly higher (p<0.05) than the cention group. It was found that from day 1 to day 7 the mean initial fluoride release has significantly reduced (p<0.05) for both the groups. Similar results were also seen when comparisons were done between day 7 to day 15 (p<0.05) and day 1 to day 15 (p<0.05) for both the groups.Conclusion:Zirconomer was more efficient in initial and fluoride re-release than the Cention N restorative material. Further in vivo studies with more parameters are recommended to evaluate fluoride release and cariostatic performance of Cention N and Zirconomer in real environmental circumstances.

How do the surface coating and one-year water aging affect the properties of fluoride-releasing restorative materials?

To evaluate the effects of surface coating and 1-year water aging on flexural strength, compressive strength (CS) and surface roughness of fluoride-releasing restorative materials. The specimens were prepared from seven materials: GCP Glass Fill (GCP), Amalgomer CR (AHL), Zirconomer (Shofu), Fuji IX GP Capsule (GC), Beautifil II (Shofu), Estelite Σ Quick (Tokuyama), and reliaFIL LC (AHL). The specimens were randomly divided into two groups for each test: surface coated with G-Coat Plus (GC) and uncoated. Each group was subdivided into two groups stored in distilled water at 37°C for 24 h and 1 year before testing (n = 10). The flexural and CS were evaluated according to ISO standards on a universal testing machine. The surface roughness was assessed with AFM. After flexural strength test, a cross-section of the coated specimens was evaluated with SEM. Data were analyzed with one-way analysis of variance, Duncan and independent t-tests (P = 0.05). After 24 h, a significant increase was observed on the flexural and CS of Amalgomer CR, Zirconomer, and Fuji IX GP by coating (P < 0.05). After 1 year, the coating increased the flexural strength of Amalgomer CR and Zirconomer, and CS of GCP Glass Fill (P < 0.05). The coating decreased the surface roughness of GCP Glass Fill, Amalgomer CR, and Zirconomer after 1 year (P < 0.05). The water aging decreased the mechanical properties of glass ionomer-based materials and increased their surface roughness (P < 0.05). The mechanical properties and surface roughness of glass ionomer-based materials were affected by coating and water aging.

The effect of ionizing radiation on properties of fluoride-releasing restorative materials

The purpose of this study was to evaluate the effect of ionizing radiation from high energy X-ray on fluoride release, surface roughness, flexural strength, and surface chemical composition of the materials. The study groups comprised five different restorative materials: Beautifil II, GCP Glass Fill, Amalgomer CR, Zirconomer, and Fuji IX GP. Twenty disk-shaped specimens (8x2 mm) for fluoride release and 20 bar-shaped specimens (25 x 2x 2 mm) for flexural strength were prepared from each material. Each material group was divided into two subgroups: irradiated (IR) and non-irradiated (Non-IR). The specimens from IR groups were irradiated with 1.8 Gy/day for 39 days (total IR = 70.2 Gy). The amount of fluoride released into deionized water was measured using a fluoride ion-selective electrode and ion analyzer after 24 hours and on days 2, 3, 7, 15, 21, 28, 35, and 39 (n = 10). The flexural strength was evaluated using the three-point bending test (n = 10). After the period of measurement of fluoride release, seven specimens (n = 7) from each group were randomly selected to evaluate surface roughness using AFM and one specimen was randomly selected for the SEM and EDS analyses. Data were analyzed with two-way ANOVA and Tukey tests (p = 0.05). The irradiation significantly increased fluoride release and surface roughness for Amalgomer CR and Zirconomer groups (p < 0.05). No significant change in flexural strength of the materials was observed after irradiation (p > 0.05). The ionizing radiation altered the amount of fluoride release and surface roughness of only Amalgomer CR and Zirconomer. The effect could be related to the chemical compositions of materials.

FLUORIDE RELEASE AND RERELEASE AFTER RECHARGING OF TWO HYBRID RESIN RESTORATIONS IN PRIMARY TEETH. “A COMPARATIVE IN VITRO STUDY”.

INTRODUCTION: Fluoride-releasing restorative materials can be used as a reservoir releasing small amounts of fluoride to the teeth over a long time.Giomer represents a new class of dental materials that uses the pre reacted glass technology (PRG) with excellent mechanical and esthetic properties. OBJECTIVES: The aim of this study is to evaluate the fluoride release ability of Giomer (Beautifil II) compared to Compomer (Dyract XP) and their fluoride recharge ability after exposure to topical fluoride varnish. MATERIALS AND METHODS: The sample consisted of 80 freshly extracted primary anterior teeth. Standardized buccal class V cavities were prepared. Sample was randomly divided into 2 groups: Group I: included 40 teeth restored with Beautiful II. Group II: included 40 teeth restored with Dyract XP following the manufacturer’s guidelines. Fluoride release was evaluated in the artificial saliva on 1st, 7th, 14th and 21st days. After 21days of release, 5%NaF varnish was applied on buccal surface of all specimens. The amount of fluoride release after recharge was measured in the artificial saliva after 1st, 7th, 14th and 21st days using fluorine ion- specific electrode. Data were analyzed using Friedman’s two-way analysis of variance by ranks, Dunn-Sidak method, Mann-Whitney U test and Wilcoxon Signed Ranks to achieve the aim of the study. RESULTS: Beautiful II released significantly higher amount of fluoride compared to Dyract XP in first 7 days at p0.0125. CONCLUSIONS: Fluoride release (ppm) was found to be significantly higher in Beautiful II than Dyract XP in the first week. Giomer could be considered a suitable class V restoration of primary teeth in high caries risk children.

Evaluation of Restorative Materials Containing Preventive Additives in a Secondary Caries Model in vitro

The incorporation of antibacterial agents into dental restorative materials is a promising strategy for secondary caries prevention. Previously, Carolacton affected Streptococcus mutans biofilm formation on composite materials in vitro. The present study evaluated secondary caries formation adjacent to Carolacton-containing composites and conventional restorative materials using an artificial biofilm model. Standardized cavities were prepared in bovine dentin-enamel samples (n = 175) and restored with various dental materials (Tetric EvoCeram [T], GrandioSo composite without [G] and with Carolacton [GC], Grandio Flow without [F] and with Carolacton [FC], GrandioSo containing sodium fluoride [GNaF], and Ketac Fil [K]). After artificial aging, S. mutans was grown on the samples for 7 days. The investigation of gap sizes and secondary caries formation was performed using confocal laser scanning microscopy and transversal microradiography. Median gap size in enamel was 9.4 µm (interquartile range 7.9–12.7). Compared to all other groups significant differences in gap sizes could be observed for Ketac Fil (p < 0.001; Mann-Whitney test). Only GrandioSo composite containing 30% sodium fluoride and Ketac Fil showed significantly smaller lesion areas in enamel (p < 0.001; Mann-Whitney test) than all other groups which was confirmed by the mineral loss data (p < 0.001; Mann-Whitney test). Based on the present in vitro results, it seems that Carolacton-containing composite in the current formulation within the shown simplified monoculture biofilm model is not able to prevent caries formation compared to fluoride-releasing restorative materials.

Comparative evaluation of the effect of a saliva substitute on the color stability of three different direct tooth-colored restorative materials: Anin vitrospectrophotometric study

Context: An aesthetic restorative material that would be suitable to be used in patients who are prescribed saliva substitute (SS) for symptomatic relief from xerostomia. Aims: This study aimed to evaluate and compare the effect of SS on the color stability of three different direct tooth-colored restorative materials. Settings and Design: This is an in vitro spectrophotometric study where standard uniform disc-shaped specimens were immersed in a SS for 30 days. Materials and Methods: The materials investigated were resin-modified-glass ionomer cement (RM-GIC), light-cured (LC) resin composite restorative material (Filtek™ Z350 XT), and LC fluoride-releasing restorative material (Ketac™ N100). Sixteen disc-shaped samples of each test material were prepared using a polytetrafluoroethylene mold, making up a total of 48 samples and were assigned to three groups: Group I (RM-GIC), Group II (Filtek™ Z350 XT), and Group III (Ketac™ N100). They were further divided into two subgroups A and B with eight samples each based on the immersion solutions namely distilled water (DW) and SS, respectively. The samples were immersed for 30 days. Baseline and postimmersion color analysis was done with a spectrophotometer. The CIE L*a*b* values were measured and CIE ΔE values obtained were tabulated. Statistical Analysis Used: The data obtained were statistically analyzed using ANOVA and independent t-test, and the pair-wise significance between groups was obtained using least significant difference test. P 3.3) than the samples immersed in DW and was found to be statistically significant (P

Microhardness and SEM-EDX Analysis of Permanent Enamel Surface Adjacent to Fluoride-releasing Restorative Materials Under Severe Cariogenic Challenges.

In this study, the protective effects of restorative materials with fluoride content, resin-modified glass-ionomer cement (RMGIC), giomer, and glass carbomer against artificial initial caries lesions in a simulated highly cariogenic oral environment were evaluated. Considering the reported recharging abilities of these restorative materials, fluoridated toothpaste was applied to some groups, in which the anti-demineralising effect was also evaluated. Two enamel blocks were produced from each of 60 sound permanent molars. Sixty specimens were used for microhardness analysis, and the rest were used for SEM-EDX analysis. Enamel specimens were randomly assigned to three groups according to the restorative material: A = resin-modified glass-ionomer cement; B = giomer; C = glass carbomer. Artificial initial caries lesions were created using demineralising solutions, after which specimens were exposed to in vitro pH cycling simulating a highly cariogenic oral environment. Microhardness and mineral analyses were performed on the enamel surrounding the restorative materials at three different times during the experiment: at the beginning of the experiment, then after the creation of the artificial early caries lesions, and finally after pH cycling. Microhardness and SEM-EDX results mostly confirmed each other. RMGIC and glass carbomer groups with added fluoride toothpaste showed statitsically significantly better anti-demineralising effects in comparison to other groups. Neither of the giomer groups performed as well as RMGIC or glass carbomer. Because of the similarity between the demineralisation inhibitory activity of glass carbomer and RMGIC, glass carbomer may be preferred as a restorative material in paediatric dentistry.

Comparative evaluation of fluoride release and recharge potential of novel and traditional fluoride-releasing restorative materials: An in vitro study.

Aim:The aim of this study was to evaluate and compare the fluoride ion release and uptake of glass ionomer cement GP IX Extra (GE), EQUIA® Forte Fil (EF), Beautifil Bulk (BB), Dyract® XP (DXP), Tetric N-Ceram® (TNC) in vitro.Materials and Methods:The restorative materials were divided into five groups (n = 12), namely G1 – GE, G2 – EF, G3 – BB, G4 – DXP, G5 – TNC. Fluoride release was checked using fluoride ion-selective electrode (Orion 9609BNWP, Ionplus Sure-Flow Fluoride, Thermo Scientific, USA) at time intervals of 1 day and thereafter at 3, 7, 14, 21, and 28 days. Following this, fluoride recharge was done with 1.23% acidulated phosphate fluoride gel (12,300 ppm, Pascal International Inc., 2929 Northup Way, Bellevue, USA) after 28 days and each sample was re-checked for fluoride release at the same time intervals.Statistical Analysis:One-way ANOVA with post hoc Games–Howell test for intergroup and repeated measures ANOVA with post hoc Bonferroni test for intragroup analysis. P < 0.05 was considered statistically significant.Results:On intergroup analysis, Group 2 showed high values of fluoride release and recharge at all-time intervals which were significantly higher (P < 0.001) than Groups 1, 3, 4 and 5. Intragroup analysis showed significantly higher (P < 0.001) fluoride release and recharge at the end of day 1 which decreased progressively with time for all the tested materials.Conclusion:EF showed the highest fluoride release and recharge potential across all time intervals compared to other tested restorative materials and the greatest fluoride release was seen on day 1.

Characterization of fluoride releasing restorative dental materials.

This study aimed to evaluate and compare certain mechanical properties, Vickers-hardness, water sorption, fluoride-release, shrinkage-stress and wear of five commercial fluoride-releasing restorative materials (Dyract, CompGlass, BEAUTIFIL II, ACTIVA-Restorative, and GC Fuji II LC), in relation to their microstructural characteristics. Mechanical properties were determined for each material following ISO standards. A wear test was conducted with 15,000 chewing cycles using a dual-axis chewing simulator. Daily fluoride-release was measured during the first 10 days by using a fluoride ion selective electrode. Scanning electron microscopy (SEM) was used to evaluate the microstructure of each material. Results were statistically analysed using ANOVA followed by post hoc Tukey's test. ACTIVA-Restorative exhibited the highest fracture toughness (1.1 MPa m1/2) among the materials tested. BEAUTIFIL II presented the highest flexural strength (145 MPa) which was not significantly different (p>0.05) from CompGlass and Dyract. Highest fluoride-release measurement was located for GC Fuji II LC among other tested materials.