Physical properties of glass ionomer cement containing pre-reacted spherical glass fillers

Abstract The aim of this study was to assess the effect of different commercial liquid phases (Ketac, Riva, and Fuji IX) and the use of spherical pre-reacted glass (SPG) fillers on cement maturation, fluoride release, compressive (CS) and biaxial flexural strength (BFS) of experimental glass ionomer cements (GICs). The experimental GICs (Ketac_M, Riva_M, FujiIX_M) were prepared by mixing SPG fillers with commercial liquid phases using the powder to liquid mass ratio of 2.5:1. FTIR-ATR was used to assess the maturation of GICs. Diffusion coefficient of fluoride (DF) and cumulative fluoride release (CF) in deionized water was determined using the fluoride ion specific electrode (n=3). CS and BFS at 24 h were also tested (n=6). Commercial GICs were used as comparisons. Riva and Riva_M exhibited rapid polyacrylate salt formation. The highest DF and CF were observed with Riva_M (1.65x10-9 cm2/s) and Riva (77 ppm) respectively. Using SPG fillers enhanced DF of GICs on average from ~2.5x10-9 cm2/s to ~3.0x10-9 cm2/s but reduced CF of the materials on average from ~51 ppm to ~42 ppm. The CS and BFS of Ketac_M (144 and 22 MPa) and Fuji IX_M (123 and 30 MPa) were comparable to commercial materials. Using SPG with Riva significantly reduced CS and BFS from 123 MPa to 55 MPa and 42 MPa to 28 MPa respectively. The use of SPG fillers enhanced DF but reduced CF of GICs. Using SPG with Ketac or Fuji IX liquids provided comparable strength to the commercial materials.

Resumo O objetivo deste estudo foi avaliar o efeito de diferentes fases líquidas comerciais (Ketac, Riva e Fuji IX) e o uso de partículas esféricas de vidro pré-reagido (SPG) na maturação do cimento, liberação de flúor, força de compressão (CS) e resistência biaxial à flexão (BFS) de cimentos de ionômero de vidro (GICs) experimentais. Os GICs experimentais (Ketac_M, Riva_M, FujiIX_M) foram preparados pela mistura de partículas SPG com fases líquidas comerciais usando a proporção de pó para massa líquida de 2,5: 1. O FTIR-ATR foi usado para avaliar a maturação dos GICs. O coeficiente de difusão do flúor (DF) e a liberação cumulativa de flúor (CF) em água deionizada foram determinados usando o eletrodo específico do íon fluoreto (n = 3). CS e BFS em 24 h também foram testados (n = 6). GICs comerciais foram usados como comparações. Riva e Riva_M exibiram rápida formação de sal de poliacrilato. Os maiores DF e CF foram observados com Riva_M (1,65x10-9 cm2/s) e Riva (77 ppm), respectivamente. O uso de partículas SPG melhorou o DF de GICs em média de ~ 2,5x10-9 cm2/s a ~ 3,0x10-9 cm2/s, mas reduziu o CF dos materiais em média de ~ 51 ppm a ~ 42 ppm. O CS e BFS de Ketac_M (144 e 22 MPa) e Fuji IX_M (123 e 30 MPa) foram comparáveis aos materiais comerciais. Usar SPG com Riva reduziu significativamente CS e BFS de 123 MPa para 55 MPa e 42 MPa para 28 MPa, respectivamente. O uso de SPG partículas melhorou o DF, mas reduziu o CF dos GICs. O uso de partículas SPG com líquidos Ketac ou Fuji IX proporcionou resistência comparável aos materiais comerciais.

Evaluation of mechanical properties of fluoride-releasing dental materials after multiple fluoride recharge/discharge application / Avaliação das propriedades mecânicas de materiais dentários liberadores de flúor após aplicação múltipla de recarga/descarga de flúor

This study aimed to determine the mechanical properties of fluoride-releasing dental materials after an accelerated fluoride recharge/discharge procedure. Two fluoride-releasing glass ionomer types of cement (Ketac Molar Easymix and IonoStar Molar), a resin-modified glass ionomer (Photac Fil Quick Aplicap), and two compomers (Compoglass F and Glasiosite) were used in this study. A total of 30 rectangular specimens and 30 disk specimens of each material were prepared and placed in distilled/deionized water (n = 5). The amount of fluoride released was analyzed from the materials for 7-day discharge, 1st recharge, 7-day discharge, 2nd recharge, and 7-day discharge, and 3rd recharge. The de/pre- and post-recharge fluoride release were measured using an ion chromatography for 24 days. The flexural strength and microhardness of each group were evaluated. The microhardness of all restorative materials showed no significant change (p > 0.05) over the experimental period. The flexural strength properties of the restorative materials did not change within the time of the study. The study showed that the fluoride release/uptake causes no effect on the mechanical and physical properties of dental materials.

Este estudo teve como objetivo determinar as propriedades mecânicas de materiais dentários liberadores de flúor após um procedimento acelerado de recarga/descarga de flúor. Dois tipos de cimento de ionômero de vidro liberador de flúor (Ketac Molar Easymix e IonoStar Molar), um ionômero de vidro modificado por resina (Photac Fil Quick Aplicap) e dois compômeros (Compoglass F e Glasiosite) foram utilizados neste estudo. Um total de 30 amostras retangulares e 30 amostras de disco de cada material foram preparadas e colocadas em água destilada/deionizada (n = 5). A quantidade de fluoreto liberado foi analisada a partir dos materiais para descarga em 7 dias, 1ª recarga, descarga em 7 dias, 2ª recarga e descarga em 7 dias e 3ª recarga. A liberação de fluoreto pré e pós-recarga foi medida usando uma cromatografia de íons por 24 dias. A resistência à flexão e a microdureza de cada grupo foram avaliadas. A microdureza de todos os materiais restauradores não apresentou alteração significativa (p > 0,05) durante o período experimental. As propriedades de resistência à flexão dos materiais restauradores não mudaram no período do estudo. O estudo mostrou que a liberação/captação de flúor não afeta as propriedades mecânicas e físicas dos materiais dentários.

Formulation and characterization of antibacterial orthodontic adhesive

ABSTRACT Objective: The objective of this study was to formulate experimental orthodontic bracket adhesives and test their mechanical properties, fluoride release and antibacterial activity. Methods: Four experimental antibacterial orthodontic bracket adhesives were prepared with different compositions of synthesized antibacterial monomers replacing total 5% of dental monomers in the control Transbond XT (3M): 5%C11, 3.5%C11+1.5%C2, 5%C16, and 3.5%C16+1.5%C2. Transbond XT alone was used as control. These groups were used to bond premolar brackets to extracted premolars. Shear bond strength (SBS) was tested using an Instron machine. For antibacterial test, disk specimens (10mm diameter, 1mm thick, n=4) were fabricated and incubated with cultures of cariogenic Streptococcus mutans for 48h, and following gentle sonication, S. mutans biofilms in colony-forming-units (CFU) on the disks were enumerated by plating on agar medium. The data were analyzed using ANOVA and Tukey test (α=0.05). Results: All experimental groups had similar shear bond strength (no significant difference) to the control. All experimental groups showed significant inhibitory effect against S. mutans biofilm formation, when compared to the control, but there was no significant difference between experimental groups. Conclusion: Antibacterial orthodontic adhesive can be fabricated to have similar mechanical properties but better caries-inhibitory effect than current adhesive.

RESUMO Objetivo: o objetivo do presente estudo foi formular, experimentalmente, adesivos para colagem de braquetes ortodônticos e testar as suas propriedades mecânicas, sua liberação de flúor e sua atividade antibacteriana. Métodos: quatro adesivos ortodônticos antibacterianos foram preparados experimentalmente usando monômeros sintéticos antibacterianos com diferentes composições, substituindo-se 5% do monômero do grupo controle (Transbond XT, 3M) por: 5%C11; 3,5%C11 + 1,5%C2; 5%C16; ou 3,5%C16 + 1,5%C2. O Transbond XT original foi utilizado como controle. Esses diferentes adesivos foram usados para colar braquetes de pré-molares em pré-molares extraídos. A resistência da colagem ao cisalhamento (RCC) foi testada utilizando-se uma máquina Instron. Para os testes antibacterianos, amostras em formato de disco (10 mm de diâmetro, 1 mm de espessura, n = 4) foram fabricadas e incubadas por 48 horas com culturas cariogênicas de Streptococcus mutans. Após leve sonicação, os discos contendo os biofilmes de S. mutans em unidades formadoras de colônia (UFC) foram colocados em placas com meio de cultura ágar e numerados. Os dados foram analisados utilizando-se ANOVA e teste de Tukey (α?#8197;= 0,05). Resultados: todos os grupos experimentais apresentaram RCC semelhante (sem diferença significativa) ao grupo controle. Todos os grupos experimentais apresentaram significativo efeito inibitório contra a formação do biofilme de S. mutans, em comparação ao grupo controle, porém sem diferença significativa entre os grupos experimentais. Conclusão: adesivos ortodônticos antibacterianos podem ser produzidos para alcançar propriedades mecânicas semelhantes às dos adesivos atuais, porém com melhores efeitos inibitórios de cáries.

Effects of fluoride release and solubility of resin modified glass ionomer with surface coating agents

PURPOSE: This study aimed to investigate the correlation between the solubility and the amount of fluoride release when a resin surface coating agent is applied to RMGIC. MATERIALS AND METHODS: To measure the fluoride release and solubility, Fuji II LC®and Filtek™ Z350XT without a surface coating, Fuji II LC® with G coat plus™ and Fuji II LC® with Permaseal® were prepared. And the amount of fluoride release and solubility were measured. RESULTS: There was no significant difference in the daily fluoride release between the surface coating agents. The cumulative fluoride release was significantly different between the groups using RMGIC at 56 days (P < 0.05). In the solubility measurement, RMGIC without surface coating was significantly different only on the 7th day compared to the other three groups (P < 0.05). CONCLUSION: Surface coating agents can prevent the degradation of properties by the initial solvent in RMGIC. Therefore, fluoride is preserved inside the restorative material and the effect of surface coating after the addition is reduced, so that the effect on fluoride release and storage is also reduced.

In vitro fluoride release from five different fluoride varnishes / 대한구강보건학회지

OBJECTIVES: This study aims to compare the fluoride-release between different fluorine varnish under in vitro experimental conditions.METHODS: In this study, 5 fluoride varnish products distributed in Korea were selected. V-varnish™ (Vericom, Korea: VV), CavityShield™ (3M ESPE, USA: CS), Clinpro™ White varnish™ (3M ESPE, USA: CP), MI Varnish™ (GC, Japan: MI), and Fluor Protector (Ivoclar Vivadent, Liechtenstein: FP). For the in vitro study, 10 mg of each fluoride varnish was thinly applied to the same area of the specimen. The specimen was then immersed in 3 ml of distilled water at consistent intervals to confirm fluoride release. Nine specimens per group were used. Fluoride ion electrodes were used to measure the fluoride concentration of the solution. The Kruskal-Wallis nonparametric test was performed to compare between each experimental group, and the Wilcoxon signed-rank nonparametric test was performed to compare experimental groups over time. The significance level for a Type I error was set at 0.05. All statistical analyses were performed using SPSS 25.0 (IBM Co., Armonk, NY, USA).RESULTS: In vitro experiments showed that the amount of fluoride released from MI was higher than the other groups during the first 12 hours after application. However, the amount of fluoride released from CP and CS was higher than MI as the immersion time increased over 12 and 20 hours, respectively. The fluoride release from FP was the lowest at all measurement points.CONCLUSIONS: The results of this study showed that the remaining fluoride effect from rosin type fluoride varnishes was higher than liquid type fluoride varnishes. There were differences in the residual fluoride concentrations despite each fluoride varnish having the same fluoride content.

Effect of casein phosphopeptide-amorphous calcium phosphate on fluoride release and micro-shear bond strength of resin-modified glass ionomer cement in caries-affected dentin

OBJECTIVES: This study was conducted to evaluate fluoride release and the micro-shear bond strength of resin-modified glass ionomer cement (RMGIC) in casein phosphopeptide-amorphous calcium phosphate (CPP-ACP)-remineralized caries-affected dentin (CAD). MATERIALS AND METHODS: Exposed dentin surfaces of 30 human third molar teeth were divided into 2 equal groups for evaluating fluoride release and the micro-shear bond strength of RMGIC to CAD. Each group was subdivided into 3 equal subgroups: 1) control (sound dentin); 2) artificially demineralized dentin (CAD); 3) CPP-ACP remineralized dentin (remineralized CAD). To measure fluoride release, 15 disc-shaped specimens of RMGIC (4 mm in diameter and 2 mm in thickness) were bonded on one flat surface of the dentin discs of each group. Fluoride release was tested using ion chromatography at different intervals; 24 hours, 3, 5, 7 days. RMGIC micro-cylinders were built on the flat dentin surface of the 15 discs, which were prepared according to the assigned group. Micro-shear bond strength was measured after 24 hours water storage. Data were analyzed using 1- and 2-way analysis of variance and the post hoc least significant difference test (α = 0.05). RESULTS: Fluoride detected in solutions (at all intervals) and the micro-shear bond strength of RMGIC bonded to CPP-ACP-remineralized dentin were significantly higher than those bonded to artificial CAD (p < 0.05). CONCLUSIONS: Demineralized CAD consumes more fluoride released from RMGIC into the solution for remineralization than CPP-ACP mineralized dentin does. CPP-ACP increases the micro-shear bond strength of RMGIC to CAD.

Newer Advances In Glass Ionomer Cement: A Review

Glass Ionomer Cement has its origin in the mid twentieth century, as a biocompatible, cost effective, tooth coloured restorative material and is in constant evolution. Considering its unique ability to bond to the tooth structure without the use of any bonding agent coupled with fluoride releasing potential, GIC has gradually emerged as material of choice for various applications in the field of dentistry. This article elaborates on the composition of GIC and its recent advances which have markedly improved their properties for optimal incorporation of these materials into various restorative treatment procedures.

Streptococcus Mutans Biofilm Influences on the Antimicrobial Properties of Glass Ionomer Cements

Abstract The aim of this study was to evaluate the in vitro antibacterial and biofilm inhibition properties of glass ionomer restorative cements. Ketac Nano, Vitremer, Ketac Molar Easymix and Fuji IX were analyzed using the following tests: a) agar plate diffusion test to evaluate the inhibitory activity of cements against S. mutans (n=8); b) S. mutans adherence test by counting colony-forming units after 2 h of material/bacteria exposure (n=10); c) biofilm wet weight after seven days of bacterial accumulation on material disks, with growth medium renewed every 48 h (n=10); d) pH and fluoride measurements from the medium aspired at 48 h intervals during the 7-day biofilm development (n=10). Data from the a, b and c tests were submitted to Kruskal-Wallis and Mann-Whitney tests and the fluoride-release and pH data were submitted to two-way ANOVA and Tukey tests (a=5%). Vitremer followed by Ketac Nano showed the greatest inhibitory zone against S. mutans than the conventional ionomers. Vitremer also showed higher pH values than Ketac Nano and Fuji IX in the first 48 h and released higher fluoride amount than Ketac Nano e Ketac Molar Easymix throughout the experimental period. The chemical composition of restorative glass ionomer materials influenced the antibacterial properties. The resin modified glass ionomer (Vitremer) was more effective for inhibition of S. mutans and allowed greater neutralization of the pH in the first 48 h. However, the type of glass ionomer (resin modified or conventional) did not influence the weight and adherence of the biofilm and fluoride release.

Resumo O objetivo neste estudo foi avaliar in vitro as propriedades antibacterianas e a inibição do biofilme de cimentos de ionômero de vidro restauradores. Ketac Nano, Vitremer, Ketac Molar Easymix and Fuji IX foram avaliados através dos seguintes testes: a) teste de difusão em ágar para avaliar a inibição de S. mutans nos cimentos (n=8); b) adesão de S. mutans pela contagem de unidades formadoras de colônia após 2h de exposição material/bactéria (n=10); c) peso do biofilme úmido após sete dias de acúmulo bacteriano nos discos do material, com meio de cultura renovado após 48 h (n=10); d) mensuração do pH e liberação de flúor do meio aspirado nos intervalos de 48 h durante 7 dias de crescimento do biofilme (n=10). Os dados dos testes a, b e c foram submetidos aos testes Kruskal-Wallis e Mann-Whitney e os dados de liberação de flúor e pH a ANOVA dois fatores e Tukey (a = 5%). Vitremer seguido pelo Ketac Nano mostrou maior zona de inibição contra S. mutans quando comparados aos ionômeros convencionais. Vitremer também apresentou valores de pH mais elevados do que Ketac Nano e Fuji IX nas primeiras 48 h e liberou maior quantidade de flúor do que Ketac Nano e Ketac Molar Easymix durante todo o período experimental. A composição química dos ionômeros de vidro restauradores influenciou nas propriedades antibacterianas. O ionômero de vidro modificado por resina (Vitremer) foi mais eficaz na inibição de S. mutans e permitiu maior neutralização do pH nas primeiras 48 h. No entanto, o tipo de ionômero de vidro (modificado por resina ou convencional) não influenciou no peso e adesão do biofilme e na liberação de flúor.

Study on preparation and fluoride-relesae properties of fluorinated nanosilica filler / 医学研究生学报

Objective The aim of the study was to develop a kind of new fluoride composite resin .We explored the practica-bility of preparing fluorinated filler by using hollow silica microsphere as a carrier of sodium fluoride (NaF) as well as its fluoride-re-lease properties in composite resin . Methods Hollow silica microspheres with mesoporous shells were prepared by the sacrificial template method.NaF was loaded into hollow silica microspheres by the impregnation method .Scanning electron microscopy ( SEM) was used to determine the morphologies of hollow silica microspheres before and after NaF loading .Hollow nanosilica microsphere con-taining NaF and NaF powder were respectively mixed with resin at the same intial NaF concentration of 13.9, 27.8 and 55.6 mg/mL for comparison, which were taken as the experiment group and the control group .The samples were put into 100 mL artificial saliva at 37℃to caculate the cumulative fluoride release quantities from 1 d to 47 d.Results The morphology of hollow microsphere did not chang significantly before and after NaF loading .In the experiment group ,the cumulative quantities of fluoride release were 0.026, 0.105, 0.21 mg/cm 2on 1 d and increased to 0.088, 0.239, 0.484 mg/cm 2on 47 d according to respective initial NaF concentration . While in the control group, the corresponding figures were 0.006, 0.025, 0.04 mg/cm2on 1 d and 0.022, 0.045, 0.056 mg/cm2on 47 d.The difference between these two groups was of great statistical significance . Conclusion Hollow silica microsphere could be used as a carrier of NaF .Fluorinated nanosilica filler using hollow microsphere promotes the fluoride release in composite resin .

Dentin Bond Strength of a Fluoride-Releasing Adhesive System Submitted to pH-Cycling

To evaluate the microtensile bond strength (µTBS) of a fluoride-containing adhesive system submitted to a pH-cycling and storage time regimen for primary outcomes. As secondary outcomes the fluoride released amount was evaluated. Twelve dentin surfaces from sound third molar were divided into 2 groups according to adhesive systems: Clearfil SE Protect (PB) and Clearfil SE Bond (SE). Sticks obtained (1.0 mm2) from teeth were randomly divided into 3 subgroups according to storage regimen model: immediate (24h); 5-month deionized water (W); and pH-cycling model (C). All sticks were tested for µTBS in a universal testing machine. Fluoride concentration was obtained from 1-4 days and 30-day in W and 1-4 days in demineralization (DE)/remineralization (RE) solutions from C, using a fluoride-specific electrode. µTBS and fluoride released data were, respectively, submitted to ANOVA in a split plot design and Tukey, and Friedman' tests (a=0.05). There was no significant interaction between adhesive system and storage regimen for µTBS. W showed the lowest µTBS values. There was no significant difference between 24 h and C models for µTBS. There was no significant difference between adhesive systems. Failure mode was predominantly cohesive within composite for the 24 h and W, for the C group it was mixed for SE and cohesive within composite for PB adhesive system. Fluoride concentrations in the DE/RE solutions were less than 0.03125 ppm and not detected in W. In conclusion, the fluoride-containing adhesive system performed similarly to the regular one. Hydrolytic degradation is the main problem with both adhesive systems, regardless of fluoride contents.

O objetivo principal desse estudo foi avaliar a resistência de união à microtração de dois sistemas adesivos (com e sem flúor) após a ciclagem de pH e armazenagem em água deionizada. A quantidade de flúor liberada foi avaliada secundariamente. Doze terceiros molares hígidos foram separados em 2 grupos de acordo com o sistema adesivo: Clearfil SE Protect - com flúor (PB) e Clearfil SE Bond - sem flúor (SE). Os palitos (1 mm2) obtidos do mesmo dente foram aleatoriamente divididos em 3 subgrupos de acordo com o meio de armazenagem: em água deionizada por 24h ou 5 meses e ciclagem de pH. Os palitos foram tracionados em uma máquina de ensaio universal a 0,5 mm/min. A concentração de flúor foi analisada em água deionizada (1-4 dias e 30 dias) e na solução remineralizadora e desmineralizadora (1-4 dias) usando um eletrodo específico. Os dados de resistência de união e liberação de flúor foram, respectivamente, submetidos à Análise de Variância em esquema de parcela subdividida e ao teste de Friedman (a=0,05). Não houve nenhuma interação significativa na resistência de união entre os sistemas adesivos e os meios de armazenagem. Os menores valores de resistência de união à microtração foram encontrados para os palitos armazenados em água deionizada. Não houve nenhuma diferença significativa nos valores de resistência de união após 24h e ciclagem de pH. Nenhuma diferença significativa na resistência de união foi observada entre os 2 sistemas adesivos. O modo de falha foi predominantemente coesivo em compósito para os grupos armazenados em água por 24h ou 5 meses para ambos os sistemas adesivos. No grupo submetido à ciclagem, a falha foi mista para o SE e coesiva em compósito para o PB. A concentração de flúor nas soluções DE/RE foi menor que 0,03125 ppm e não detectada em água deionizada. Concluindo, o sistema adesivo com flúor (PB) apresentou performance similar ao sistema adesivo sem flúor (SE). A degradação hidrolítica foi o principal fator para ambos os sistemas adesivos, independente da adição de flúor.

Liberación de fluoruro de dos cementos de ionómero de vidrio: estudio in vitro / Fluoride release of two glass-ionomer cements: in vitro study

Objetivo: El propósito de este estudio fue comparar la cantidad de fluoruro liberada por dos cementos de ionómero de vidrio: Ketac Molar Easymix® (3M ESPE), el cual es de reciente aparición en el mercado y ofrece la ventaja de mezclarse fácilmente, y FUJI II® (GC Dental industrial Corporation), el cual ha estado a la venta por más tiempo. Métodos: Ambos materiales se manipularon de acuerdo con las indicaciones del fabricante. Se realizaron 15 muestras de cada cemento de ionómero de vidrio, utilizando conformadores de muestras de 4 mm de diámetro por 6 mm de altura. Se colocó el cemento de ionómero de vidrio en los conformadores y se prensó. Las muestras fueron introducidas en una estufa (37 ± 1 ºC a 90% de humedad relativa). Una hora después las muestras se retiraron de la estufa y fueron inmersas individualmente en 1 mL de agua desionizada, en un recipiente de plástico sellado herméticamente. Posteriormente se almacenaron en una cámara a 37 ± 1 ºC. A las 24 horas se retiraron las muestras de la cámara y de la solución de almacenaje, se enjuagaron con agua desionizada, se eliminó el exceso de agua con papel secante y se transfirieron a otro recipiente, añadiendo 1 mL de agua desionizada para colocar las muestras en la estufa bajo las mismas condiciones. A la solución de almacenaje se le agregó la solución tampón de ajuste de la fuerza iónica total para ser leída utilizando un potenciómetro y un electrodo selectivo para fluoruros bajo agitación magnética. Para llevar a cabo la determinación de fluoruro, previamente se prepararon soluciones del mismo a diferentes concentraciones para establecer la curva de calibración. El mismo procedimiento se realizó de la manera antes descrita los 36 días que duró el estudio. Resultados: Ambos cementos liberaron fluoruro. La más alta liberación se presentó durante las primeras 24 horas para ambos cementos, declinó en el segundo día y gradualmente disminuyó con el tiempo. Los resultados fueron analizados estadísticamente utilizando la prueba Mann-Whitney, en la cual no se encontraron diferencias significativas. Conclusiones: Ambos cementos de ionómero de vidrio presentan una liberación similar de fluoruro. Los cementos de ionómero de vidrio son ideales en odontología preventiva y en la técnica restaurativa atraumática.

Objective: The aim of the present study was to compare the amount of fluoride released by two glass-ionomer cements: Ketac Molar Easymix® (3M ESPE), which has recently appeared in the market and offers the additional advantage of easy mixing, and FUJI II® (GC Dental Industrial Corporation), which has been for a longer time available in the market. Methods: Both materials were handled according to the manufacturer's instructions. 15 samples were made of each glass ionomer cement using sample molds which measured 4 mm diameter x 6 mm height. Glass ionomer cement was placed into the molds and then pressed. Samples were introduced in an oven (37 ± 1 ºC at 90% relative humidity). After one hour had elapsed, samples were withdrawn from the oven and then individually immersed in 1 mL de-ionized water in a hermetically sealed plastic container, to be later stored in a chamber at 37 ± 1 ºC. After 24 hours, samples were removed from the chamber and withdrawn from the storing solution, they were then rinsed with deionized water and excess water was removed with blotting paper. Samples were then transferred to another container adding 1 mL deionized water in order to be placed in the oven under the same conditions. Total ionic strength adjustment buffer solution was incorporated into the storing solution for it to be read with the help of a potentiometer (pH-meter) and a fluoride selective electrode for fluoride under magnetic agitation. Prior to conducting fluoride measurements, solutions were prepared in different concentrations in order to establish the calibration curve. The same procedure was performed in the aforementioned manner during the 36 days which the study lasted. Results: Both cements released fluoride. For both cements, highest release was observed during the first 24 hours. Release declined during the second day and kept gradually decreasing with time. Results were statistically analyzed using the Mann-Whitney test. No statistically significant differences were observed. Conclusions: Both glass ionomer cements exhibited similar fluoride release. Glass ionomer cement are ideal for use in preventive dentistry as well as in atraumatic restorative technique.

Evaluation of release of fluoride from dental varnishes marketed in Korea / 대한구강보건학회지

OBJECTIVES: The purpose of this study was to compare the amount and rate of cumulative fluoride released over a period of 4 h from several varnishes marketed in Korea. METHODS: The following six commercial products were studied: cavity shield (CS, 22,600 ppm F), V varnish (VV, 22,600 ppm F), enamel pro varnish (EP, 22,600 ppm F), MI varnish (MI, 22600 ppm F), fluorine care (FC, 22600 ppm F), and fluor protector N (FP, 7700 ppm F). Five samples were collected from each varnish. Further, 10 mg of each varnish were applied onto an acrylic surface (diameter, 5 mm) and then immersed in 20 mL of distilled water at 37degrees C. The fluoride concentration in each sample was then analyzed after 30 min, 1, 2, 3, and 4 h, and after 4 days of exposure. RESULTS: The cumulative amount of fluoride released by FC (5.64+/-1.10 ppm) was significantly higher than that released by other products after 30 min. FC (8.55+/-1.85 ppm) and MI (8.21+/-0.81 ppm) released a significantly higher cumulative amount of fluoride after 4 h. The cumulative rate of fluoride released by FC (47.80+/-9.35%) was significantly higher than that of other products after 30 min. FC (72.44+/-15.68%) and MI (69.54+/-6.88%) showed a higher cumulative fluoride release rate after 4 h. MI sustainably released fluoride after 4 h and demonstrated a high fluoride release rate of 95.76%. CONCLUSIONS: The cumulative amount and rate of fluoride released by several varnishes were statistically significant at each time point. This data can be used by clinicians prior to selection of dental products.

Orthodontic cements: immediate protection and fluoride release / Cimentos ortodônticos: proteção imediata e liberação de flúor

OBJECTIVES: The objective of the authors was to evaluate fluoride release of 3 glass ionomer cements with immediate protection of fluoride varnish (Cavitine, SS White), divided into 3 groups: Group M (Meron, VOCO), Group V (Vidrion C, SS White) and Group KC (Ketac-Cem, 3M ESPE). METHODS: Fluoride release was measured during 60 days by means of an ion-selective electrode connected to an ion analyzer. After 4 weeks, the test specimens were exposed to a solution of 0.221% sodium fluoride (1000 ppm of fluoride). RESULTS: Results showed that the cements reached a maximum peak of fluoride release in a period of 24 h. There was a statistically significant difference between the amount of fluoride released after the applications of fluoride among the groups from the 31st to 60th day (p> 0.05). CONCLUSION: The Vidrion C and Meron cements showed better performance to uptake and release fluoride when compared with Ketac-Cem cement.

OBJETIVO: o objetivo desse estudo foi avaliar a liberação de flúor dos seguintes três cimentos de ionômero de vidro, com proteção imediata de verniz fluoretado (Cavitine, S. S. White): Meron / VOCO (Grupo M); Vidrion C / S. S. White (Grupo V); e Ketac Cem / 3M ESPE (Grupo KC). MÉTODOS: a liberação de flúor foi medida durante 60 dias, através de eletrodo íon seletivo conectado a um analisador de íons. Após quatro semanas, os corpos de prova foram expostos a uma solução de fluoreto de sódio a 0,221% (1.000ppm de flúor). RESULTADOS: os resultados evidenciaram que os cimentos atingiram o pico máximo de liberação de flúor com 24h após a presa inicial. Houve diferença estatisticamente significativa entre os grupos, quanto à quantidade de flúor liberado após as aplicações de flúor, do 31º ao 60° dia (p > 0,05). CONCLUSÃO: os cimentos Meron e Vidrion apresentaram maior capacidade de captação e liberação de flúor, em comparação ao cimento Ketac Cem.

An Invitro Comparative Evaluation of Fluoride Release From Different Fluoride Containng Restorative Materials In Various Study Solutions.

The aim of this study was to determine the level of fluoride released from four different tooth colored restorative materials; Vitremer, Fuji II LC, Dyract and Tetric ceram in three different storage solutions; artificial saliva, De-ionized water and pH cycling system and also to compare the amount of fluoride released. Fifteen discs of each material were prepared in a Teflon mould, varnish applied, polished, then stored at 370C and 100% relative humidity for a day. Each storage solution of 2 ml was pipetted into five polypropylene tubes and five samples of each material were suspended individually and the fluoride released was measured using an Orion fluoride Specific Electrode and Digital Ion Analyzer. All the results were statistically analyzed and was concluded that vitremer showed the highest fluoride release followed by Fuji II LC, Dyract and Tetric Ceram in the pH cycling system followed by De-ionized water and least in Artificial saliva.

Long-term fluoride release from resin-reinforced orthodontic cements following recharge with fluoride solution

The aim of this study was to test the hypothesis that there is no difference in the fluoride release behavior of resin-reinforced glass ionomer cements before or after fluoride recharge. The materials were divided into 5 groups: 2 resin-reinforced glass ionomer cements used for attaching orthodontic bands, that is, group FOB (Fuji Ortho Band) and group MCB (Multi-Cure Glass Ionomer Orthodontic Band Cement); 2 resin-reinforced glass ionomer cements and a composite used for bonding orthodontic brackets, that is, group OGLC (Ortho Glass LC), group FOLC (Fuji Ortho LC), and group TXT (Transbond XT), respectively. Fluoride release was measured during a 60-day period by using selective ion electrodes connected to an ionic analyser. After 4 weeks, the samples were exposed to 0.221 percent sodium fluoride solution. The results showed that cements achieved a maximum fluoride release 24 h after initial setting. No statistically significant differences were observed between groups FOB and OGLC regarding the amount of released fluoride following fluoride recharge from day 31 to day 36 (p>0.05). In conclusion, FOB and OGLC cements showed a higher capacity of capturing and releasing fluoride compared to the other cements studied.

O objetivo deste estudo foi testar a hipótese que não há diferença no desempenho dos cimentos de ionômero de vidro reforçados com resina entre si quanto à liberação de flúor antes e após recarga com flúor. Os materiais foram divididos em 5 grupos: 2 cimentos de ionômero de vidro reforçados com resina utilizados para cimentação de bandas ortodônticas: Grupo FOB (Fuji Ortho Band) e Grupo MCB (Multi-Cure Glass Ionomer Orthodontic Band Cement); 2 cimentos de ionômero de vidro reforçados com resina e 1 compósito utilizados para colagem de bráquetes ortodônticos: Grupo OGLC (Ortho Glass LC), Grupo FOLC (Fuji Ortho LC); e Grupo TXT (Transbond XT), respectivamente. A liberação de flúor foi medida durante 60 dias, através de eletrodo íon seletivo conectado a um analisador de íons. Após 4 semanas, os corpos de prova foram expostos a solução de fluoreto de sódio à 0,221 por cento. Os resultados evidenciaram que os cimentos atingiram o pico máximo de liberação de flúor com 24 h após presa inicial. Não houve diferença estatisticamente significante entre a quantidade de flúor liberado após as recargas de fluoreto de sódio entre os grupos FOB e OGLC do 31° ao 36° dia (p>0.05). Concluindo os cimentos FOB e OGLC apresentaram maior capacidade de captação e liberação de flúor comparada aos outros CIVRRs.

Fluoride release frompolyacid modified composites (compomers) in artificial saliva and lactic acid / Liberação de flúor por compósitos poliácidos modificados (compômeros) em saliva artifical e ácido lático

OBJECTIVES: The aim of this study was to assess the effect of different extraction media and time on the amount and pattern of fluoride release from compomers. MATERIAL AND METHOD: 42 specimens (n = 7 per group) in disc forms (7 mm diameter, 2 mm thickness) from three different compomers (were placed in artificial saliva (pH = 7.0) and lactic acid (pH = 5.2). The amount of the fluoride in these solutions were measured at 1st, 7th, 14th, 21th and 28th day time intervals by means of the fluoride ion selective electrode. The fluoride amount was calculated by concentration (ppm). The amount and the pattern of fluoride release was dependent on both the material, the storage medium and time. RESULTS: Fluoride release was evident for all the compomers but the rate of release varied considerably between the materials. Significant differences were also found between the different types of compomer (p < 0.01). A time dependent increase in the fluoride content was observed for all the compomers in both media. For all the tested materials, the fluoride release was higher in the lactic acid (p < 0.01). The amount of fluoride release was the most from Compoglass followed by Dyract AP and Glasiosite at 28th days, in both artificial saliva and lactic acid respectively. The least amount of fluoride release was observed at the first day.

OBJETIVOS: O objetivo deste estudo foi determinar o efeito de diferentes meios e tempo na quantidade e padrão de liberação de flúor por compômeros. MATERIAL E MÉTODO: 42 espécimes (n = 7 por grupo) em discos (7 mm de diâmetro, 2 mm de espessura), três compômeros diferentes, foram colocados em saliva artificial (pH 7,0) e ácido lático (pH 5,2). A quantidade de flúor nas soluções foram medidas a intervalos semanais, do 1º ao 28º dias (quatro semanas) por meio de eletrodos seletivos para íons flúor. A quantidade de flúor foi calculdada por concentração(ppm). A quantidade e o padrão da liberação de flúor variou consideravelmente tanto do material, do meio de armazenamento e tempo. RESULTADOS: A liberação de flúor foi evidente por todos os compômeros, mas a taxa de liberação variou consideravelmente entre os diferentes tipos de compômeros (p < 0.01). Um aumento relacionado com o tempo no conteúdo de flúor foi observado para todos os compômeros em ambos os meios. Para todos os materiais testados, a liberação de flúor foi maior no ácido lático (p < 0.01). A quantidade de liberação de flúor foi maior pelo Compoglass®, seguido pelo Duract AP® e Glasiosite® aos 28 dias, tanto na saliva artificial como no ácido lático respectivamente. A menor liberação de flúor foi observada no primeiro dia.

Avaliação in vitro da resistência ao cisalhamento e liberação de flúor de dois cimentos de ionômero de vidro reforçado por resina / In vitro evaluation of shear bond strength and fluoride release from two resin-reinforced glass ionomer cements

O objetivo deste estudo foi avaliar os cimentos de ionômero de vidro reforçados com resina Fuji Ortho LC e Fuji Ortho Band (GC América Corporation, Tokyo, Japan) quanto a resistência ao cisalhamento e liberação de flúor. Para avaliação da resistência ao cisalhamento utilizou-se 60 incisivos inferiores permanentes bovinos divididos em três grupos (n = 15). No Grupo 1, 2 e 3, as colagens foram realizadas com Transbond XT, Fuji Ortho LC e Fuji Ortho Band respectivamente. Após a colagem realizou-se o ensaio de cisalhamento de toda amostra à velocidade de 0,5 mm por minuto. A liberação de flúor dos materiais foram medidas durante 28 dias (1h, 24 h, 3, 7, 14, 21 e 28 dias) através de eletrodo íon seletivo conectado a um analisador de íons. Os resultados demonstraram que quanto a resistência ao cisalhamento (MPa) houve diferenças estatísticas entre os grupos 1 e 3, 2 e 3 (p > 0,05). Quanto a liberação de flúor os resultados evidenciaram diferença estatisticamente significante entre os grupos 1 e 3 e 2 e 3 em todos os tempos (p = 0.00) e entre os grupos 1 e 2 na avaliação de 3 dias de liberação de flúor (p = 0.00). Baseado nos resultados obtidos conclui-se que os materiais Transbond XT e Fuji Ortho possuem melhor resistência ao cisalhamento por??m menor liberação de flúor quando comparado ao Fuji Ortho Band.

The objective of this study was to evaluate two resin-reinforced glass ionomer cements, Fuji Ortho LC and Fuji Ortho Band (GC América Corporation, Tokyo, Japan) in terms of shear bond strength and fluoride release. Sixty bovine permanent lower incisors were divided into three groups (n = 15). In Groups 1, 2, and 3 the bonding procedures were performed with Transbond XT, Fuji Ortho LC, and Fuji Ortho Band materials respectively. Next, the samples were submitted to bond strength testing at crosshead speed of 0.5 mm/minute. Fluoride release from such materials was measured during 28 days (1h, 24 h, 3, 7, 14, 21, and 28 days) by means of selective ion electrodes connected to an ion analyser. With respect to the shear bond strength (MPa), the results demonstrated statistical differences between groups 1 and 3 as well as between groups 2 and 3. With respect to the fluoride release, the results showed statistically significant results between groups 1 and 3 as well as between groups 2 and 3 for all time periods (p = 0.00). Also, the 3-day evaluation showed statistical differences between groups 1 and 2 regarding fluoride release (p = 0.00). Based on the results obtained in the present study, one can conclude that Transbond XT and Fuji Ortho materials have a better shear bond strength than the Fuji Ortho Band one, although the latter releases less fluoride.

Fluoride release of six restorative materials in water and pH-cycling solutions

The fluoride release of restorative materials in deionized water has been the subject of many studies, but the behavior of these materials under conditions of acid challenge that simulates the oral cavity, needs to be further explored. Therefore, the aim of this study was to evaluate the fluoride release of restorative materials in two storage protocols: deionized water and pH-cycling system (demineralizing solution-pH 4.3 and remineralizing solution-pH 7.0) for 15 days. Eight disks of each material (Vitremer™-positive control, Dyract AP, Ariston pHc, Definite®, Tetric®Ceram and Z100-negative control) were prepared (11.0 mm x 1.5 mm) and suspended individually in 4.0 mL of each solution, which were daily changed. Daily fluoride release was analyzed with an ion specific electrode (Orion 9609) by the direct method or after HMDS-facilitated diffusion, following 1, 7 and 15 days. The values obtained were converted into µgF/mm² and the data analyzed by ANOVA and Tukey's test (p< 0.05). The results showed that all materials released more fluoride in the pH-cycling system, except for Ariston pHc which maintained a constant release during the experiment. The highest fluoride release was presented by the positive control, Vitremer™ in pH-cycling and by Ariston pHc, in deionized water. The negative control Z100 and the resins Definite® and Tetric®Ceram did not present statistically significant differences.

Effects of different fluorides and their loading on the release properties of composite resin / 第三军医大学学报

Objective To evaluate the effects of different kinds of fluorides and their loading on the fluoride releasing characteristics of fluoride containing composite resins. Methods Two paste type of composite resin, containing NaF and K 2TiF 6 respectively, were prepared. The composite resins were based on Bis GMA/TEGDMA resin and loaded with fluoride at 5%, 10%, 15% and 20% by weight, and a non fluoridated composite resin was prepared as the control. Six standardized discs (6 mm?3 mm) were made of each material, and three discs of each material were stored in plastic vials containing 5 ml deionized water at 37 ℃ respectively and the others in artificial saliva. The water and the artificial saliva were changed every 24 hours. An ion selective electrode (9606BN Orion) connected to an ion analyzer (720A Orion) was used to determine the amount of fluoride released on days 8, 15, 22, 29 and 62. The data were analyzed using t tests. Results All of the fluoride containing materials demonstrated a higher fluoride release than that from non fluoride control materials. The composite resin containing NaF released significantly more fluoride than that of K 2TiF 6. All materials showed a significantly higher release of fluoride in water than in artificial saliva ( P

In vitro study on the fluoride release from glass ionomer cements and a fluoride-containing resin / 대한치과교정학회지

In order to resolve enamel demineralization around orthodontic bracket, fluoride-releasing materials, glass ionomer cements and fluoride-containing resin, were introduced in orthodontic department. There were many studies about their fluoride release, but their results were controversial. The purpose of this study was to clarify the pattern and amounts of fluoride release from glass ionomer cements and a fluoride-containing resin during 70 days in vitro. Disc shaped specimens were prepared and immersed in polyethylene tube containing 2m1 distilled deionized water. The daily amounts of the fluoride released from each specimens were measured after experiment 1 day, 3 days. 7 days, 14 days, 42 days and 70 days. They were measured by fluoride-specific electrode combined pH/ Ion meter. The following results were as follow, 1. Fluorides released from fluoride-containing resin during 1 day were significantly less than those from glass ionomer cements. 2. On experiment 70 days, mean daily amounts of fluoride released from Miracle-Mix(R) were 3.4microgram/cm2, those from Fuji GC II(R) were 2.7microgram/cm2, those from Orthobond(R) were 2.3microgram/cm2, those from Fuji GC LC(R) were 1.4microgram/cm2 and those from fluoride-containing resin, Heliomolar(R), were 0.lmicrogram/cm2. 3. There were no significant differences in daily amounts of fluoride released from between self-curing glass ionomer cements and light-curing glass ionomer cements. Amounts of released fluoride varied among commercially available products. 4. In all experimental materials, amounts of released fluoride decreased rapidly until experimental 3 days and then decreased slowly until 14 days and more slowly until 70 days.