Fluoride release of glass ionomer-based luting cements in vitro.

STATEMENT OF PROBLEM: There is considerable variation in generic formulation and in reported fluoride release from resin-modified glass ionomer luting cements. PURPOSE: This study compared fluoride release from 2 generically similar resin-modified glass ionomer luting cements (Vitremer and Advance) with release from 2 conventional glass ionomer luting cements (Ketac-Cem and Fuji I). MATERIAL AND METHODS: Ten specimen disks of each of the 4 luting cements were fabricated and immersed in deionized water in individual polystyrene jars. The jars were stored in a humidor at 37 degrees C between test periods. At the same time each day, for 28 days, fluoride release from each specimen disk was measured in parts per million by testing the storage water. RESULTS: The 4 luting cements tested showed an initial high concentration of fluoride release during the first week, followed by a gradual decrease over the study period. Vitremer luting cement demonstrated the greatest mean cumulative fluoride release in parts per million over the study period (198), followed by Fuji I (140), Ketac-Cem (110), and Advance (99) luting cements. CONCLUSIONS: Resin-modified glass ionomer luting cements showed fluoride release comparable to the conventional glass ionomer luting cements. Vitremer luting cement released more fluoride over the 28-day period than the other cements.     

Fluoride release, weight loss and erosive wear of modern aesthetic restoratives.

OBJECTIVE: In this investigation, the in vitro sustained fluoride release, weight loss and erosive wear of three conventional glass ionomer cements (Fuji IX, ChemFil Superior, Ketac-Silver), three resin-modified glass ionomer cements (Fuji II LC, Vitremer, Photac-Fil), a polyacid-modified resin composite (Dyract), and a resin composite control material (Z100) were compared. METHODS: The amounts of fluoride released and weight changes were measured for 12 weeks using a fluoride electrode with TISAB III buffer. After 12 weeks, the specimens were recharged with fluoride using 2 mL of 1.23% APF gel. The recharged specimens were assessed for the amounts of fluoride released and weight changes over another 12 weeks. At the end of the experiment, the specimens were examined with SEM and surface profilometry. RESULTS: All materials, with the exception of Z100, showed the highest initial fluoride release rates during the first 2 days, dropping quickly over 2 weeks and becoming largely stabilised after 5 weeks, in an exponential mode. The recharging of the specimens with APF gel caused a large increase in the amounts of fluoride released during the first 2 days only. Analyses for all cements showed strong correlations between mean weight loss and cumulative fluoride release over a 5-week period following the application of the APF gel. SEM and surface profilometry found that roughness increased from the polyacid-modified resin composite to the conventional glass ionomer cements. CONCLUSIONS: APF gel caused erosive wear of the glass ionomer cements especially, and the wear correlated well with the weight losses. To minimise surface erosion, APF gel should not be used on these cements, especially as the recharging effects are transitory.     

Long-term fluoride release from a glass ionomer cement,a compomer,and from experimental resin composites

The aqueous phase of glass ionomer cements enables fluoride ions to diffuse and to be released from the material. The matrix of resin composites is much less hydrophilic, and fluoride incorporated in the material is only released in small amounts. It was the purpose of the present work to study the influence of resin matrix formulation on the fluoride release from experimental, fluoride-containing resin composites. The resin composites were based on methacrylate monomers and the adduct of maleic anhydride and HEMA (2-hydroxyethyl methacrylate). The resin composites contained 1 w% or 5 w% of AlF3*3H2O. A glass ionomer cement and a compomer were used as controls. Five disks of each material were stored in distilled water at room temperature. By means of a fluoride sensitive electrode, the fluoride release from disk-shaped specimens was determined periodically over 3 years. The glass ionomer cement released the most fluoride (1.54 +/- 4 microg/cm2 after 1 year and 248 +/- 7 microg/cm2 after 3 years). The compomer released relatively little fluoride during the 1st year (30 +/- 1 microg/cm2) but after this time the rate of fluoride release became equal to that of the glass ionomer cement, resulting in a release of 122 +/- 8 microg/cm2 after 3 years. Regarding the resin composites, the fluoride release increased with the hydrophilicity and the acid character of the polymer matrix. The release, however, was significantly lower than that from the glass ionomer cement and the compomer and ranged from 1.2 +/- 0.07 to 42 +/- 3.9 microg/cm2 at 1 year and from 2.3 +/- 0.16 to 79 +/- 6 microg/cm2 at 3 years.     

Fluoride release from aged resin composites containing fluoridated glass filler.

OBJECTIVES: The aim of this study was to evaluate the fluoride release from aged resin composites containing different types of fluoridated glass filler into both deionized distilled water and lactic acid solution. METHODS: Three resin composites, UniFil S (containing fluoro-alumino-silicate glass filler), Reactmer (containing pre-reacted glass-ionomer filler) and Beautifil (containing both types of fillers) were used. A conventional glass-ionomer cement, Ketac-Fil, was used as a control. Five disk specimens of each material were prepared and aged in water for 10 weeks. After aging, specimens were immersed in deionized distilled water for a further 6 days and then in aqueous lactic acid (pH 4.0) for 2 days. This process was repeated twice more and the specimens were subsequently immersed in water for a further 12 days. Fluoride release was measured every 2 days throughout the post-aging period. RESULTS: The amount of fluoride release for aged UniFil S and Beautifil markedly increased in acid solution compared with water storage. The difference was not so great for aged Reactmer and Ketac-Fil. UniFil S and Beautifil gave significantly greater fluoride release in water following immersion in acid solution (p<0.05, two-way ANOVA and Scheffe's test), but Reactmer and Ketac-Fil showed no such increase in fluoride release after acid immersion. SIGNIFICANCE: These results suggested that the nature of the fluoridated glass filler within a resin composite and the way in which the material interacts with an acidic environment affected the amount of fluoride released.     

Fluoride release from three glass ionomers, a compomer, and a composite resin in water, artificial saliva, and lactic acid

The amounts and the pattern of fluoride release from one metal-reinforced glass ionomer cement, two resin-modified glass ionomer cements, one compomer, and one composite resin placed in double-distilled water, artificial saliva, and lactic acid were evaluated in this study. Measurements of fluoride ion release were made for a total of 105 cylindrical specimens (10 mm in diameter and 1.5 mm in height). They were taken over a period of 16 weeks at the intervals of 4, 8, 12, and 24 hours, as well as 2, 3, 7, 14, 28, 56, and 112 days. The pattern of fluoride release was similar for all of the examined materials. The greatest amount of fluoride was released from the metal-reinforced glass ionomer Argion. The resin-modified glass ionomers Vitremer, Fuji II LC; the compomer Dyract; and the composite resin Tetric followed in ranking order. The pH of the environment strongly affected the fluoride release from the materials. There was a significant difference (P < 0.001) in the amounts of fluoride released in lactic acid vs water and artificial saliva, whereas, there was no significant difference (P > 0.05) in the amounts of fluoride released in water vs artificial saliva.     

Effects of APF gel on the physical structure of compomers and glass ionomer cements

This study assessed the effect of an acidulated phosphate fluoride (APF) gel on the surfaces of eight modern esthetic restorative materials. Five specimens each of three high powder: liquid ratio conventional glass ionomer cements (ChemFlex, Fuji IX GP, Ionofil Molar), four polyacid-modified resin composites (compomers) (Compoglass F, Dyract AP, Freedom, F2000) and an alkaline glass filled resin composite (Ariston pHc) were prepared and immersed at 37 degrees C in 2 mL of artificial saliva for six weeks. The aged specimens were then coated with 1.23% APF gel for four minutes, rinsed and again immersed in artificial saliva for another six weeks. The immersed, fresh specimens for each material were then examined with SEM and surface profilometry. After APF gel application, mean surface roughness (Ra) measurements and SEMs showed that roughness increased significantly, generally from the resin composite and compomers to the conventional glass ionomer cements (p < 0.05).     

不同品牌玻璃离子水门汀氟释放的比较

目的：离体比较临床用不同品牌及固化方式的玻璃离子水门汀（ＧＩＣ）氟释放情况，为临床使用含氟充填材料防龋提供理论依据。方法：４种ＧＩＣ，分别为Ｓｈｏｆｕ，青浦，Ｃｈｅｍｆｉｌ３种化学固化型和ＶｉｔｒｅｍｅｒＴＭ光固化型ＧＩＣ，离子选择电极法测量材料在去离子水中氟释放量。结果：所有测试材料在实验期间都能在去离子水中持续释放氟，ＶｉｔｅｒｍｅｒＴＭ、Ｓｈｏｆｕ、Ｃｈｅｍｆｉｌ和青浦分别为（２１．１１±９．７６）μｇ、（８．０８±４．４３）μｇ、（６．５２±３．２８）μｇ，（１７．６７±６．９３）μｇ（Ｐ＜０．０１）。结论：不同品牌及固化方式的ＧＩＣ氟释放能力不同，树脂基因引入玻璃离子水门汀并不影响其氟释放能力。     

Effects of artificial saliva and APF gel on the surface roughness of newer glass ionomer cements

OBJECTIVES: To investigate the surface roughness changes of newer esthetic dental restorative materials with aging and acid erosion in a simulated oral environment. METHODS: The materials included two viscous conventional glass ionomer cements originally marketed for the ART approach, one resin-modified glass ionomer cement and two resin composites. Ten specimens for each material were prepared according to the manufacturers' instructions, then each specimen was immersed in 2 ml of buffered artificial saliva at 37 degrees C for three weeks. For each material, five specimens (Group B) were then coated with 1.23% acidulated phosphate fluoride (APF) gel for four minutes, rinsed and immersed again in artificial saliva for another three weeks. Gel was not applied to the Group A specimens. For each material, the surface roughness of an additional three fresh specimens and those from Groups A and B were evaluated using a profilometer and SEM. RESULTS: The resin composites showed the least effects of acidic corrosion on their surface texture. The viscous glass ionomer cements showed the greatest changes, with significantly increased surface roughness p<0.001). CONCLUSIONS: The immersion of two newer viscous GICs in a buffered artificial saliva and the single application of APF gel resulted in significantly rougher surfaces over a relatively short six-week period.     

Effect of surface treatment of prefabricated posts on bonding of resin cement

This in vitro study evaluated the effect of various surface treatments of prefabricated posts of titanium alloy (ParaPost XH), glass fiber (ParaPost Fiber White) and zirconia (Cerapost) on the bonding of two resin cements: ParaPost Cement and Panavia F by a diametral tensile strength (DTS) test. The posts received surface treatments in three categories: 1) roughening by sandblasting and hydrofluoric acid etching; 2) application of primer by coating with Alloy Primer, Metalprimer II and Silane and 3) a combination treatment in the form of roughening (sandblasting or etching) supplemented by the application of a primer or in the form of the Cojet system. After surface treatment, the post was embedded in a cylinder of resin cement (diameter = 4.0 mm, height = 4.0 mm). The surface-treated post was centered in the resin cement-filled mold with the aid of fixation apparatus. Fifteen minutes from the start of mixing the resin cement, the specimen was freed from the mold and stored in water at 37 degrees C for seven days. Following water storage, the specimen was wet-ground to a final length of approximately 3 mm. The DTS of specimens was determined in a Universal Testing Machine. The bonding of resin cement to titanium alloy posts was increased by several surface treatments of the post. However, coating with primers as sole treatment had no effect on bonding. With the DTS method applied, none of the surface treatments had an effect on the bonding to glass fiber posts. The bonding of both resin cements to zirconia posts was improved by Cojet treatment, while sandblasting, followed by silane application, improved bonding of Panavia F.     

含氟充填材料释氟吸氟和再释氟的研究

目的 为了研究含氟充填材料能否长期稳定释放氟而发挥抗龋效能,本文观察了玻璃离子水门汀和含氟复合树脂在用含氟牙膏处理前后两个时期的释氟情况。方法 第一阶段,将玻璃离子水门汀和含氟复合树脂各６个标本,分别浸泡于去离子水中,测定其在不同时间氟的放量;第二阶段。用含氟牙膏处理各标本后,再测定其在不同时间氟的释放量。结果 当这两允填材料释氟水平降低后,用含氟牙膏处理,琪 释放量明显回升     

强化氟水门汀物理性能及释放氟研究

目的：探讨市售磷酸锌水门汀、聚羧酸锌水门汀、玻璃离子水门汀粉末中添加复合氟化物制剂（Co-F）对其物理性能及氟释放的影响。方法：在上述各水门汀粉末中按质量分数添加复合氟化物0％～20％，调和水门汀测定其固化时间、抗压强度、氟离子释放量。结果：添加适量复合氟化物对水门汀的抗压强度没有影响，添加复合氟化物的玻璃离子水门汀释放氟量增加，添加复合氟化物的聚羧酸锌水门汀、磷酸锌水门汀也能够释放氟离子。添加复合氟化物对聚羧酸锌水门汀及玻璃离子水门汀固化时间有明显影响。结论：强化氟水门汀通过释放氟，使充填材料附近牙齿发挥防治继发龋作用，基于此观点强化氟水门汀是牙科应用有希望的材料。     

Effect of one-bottle adhesive systems on the fluoride release of a resin-modified glass ionomer

A dhesive systems associated to resin-modified glass ionomer cements are employed for the achievement of a higher bond strength to dentin. Despite this benefit, other properties should not be damaged. This study aimed at evaluating the short-time fluoride release of a resin-modified glass ionomer cement coated with two one-bottle adhesive systems in a pH cycling system. Four combinations were investigated: G1: Vitremer (V); G2: Vitremer + Primer (VP); G3: Vitremer + Single Bond (VSB) and G4: Vitremer + Prime & Bond 2.1 (VPB). SB is a fluoride-free and PB is a fluoride-containing system. After preparation of the Vitremer specimens, two coats of the selected adhesive system were carefully applied and light-cured. Specimens were immersed in demineralizing solution for 6 hours followed by immersion in remineralizing solution for 18 hours, totalizing the 15-day cycle. All groups released fluoride in a similar pattern, with a greater release in the beginning and decreasing with time. VP showed the greatest fluoride release, followed by V, with no statistical difference. VSB and VPB released less fluoride compared to V and VP, with statistical difference. Regardless the one-bottle adhesive system, application of coating decreased the fluoride release from the resin-modified glass ionomer cements. This suggests that this combination would reduce the beneficial effect of the restorative material to the walls around the restoration.     

A long term study of fluoride release from metal-containing conventional and resin-modified glass-ionomer cements

The objective of this study was to determine long term release of fluoride from a resin-modified glass-ionomer cement (RMGIC) (Fuji II LC (FLC)) compared with that from two conventional acid-base setting cements (HiDense (HD) and KetacSilver (KS)) marketed for similar restorative purposes. Fluoride release from discs of cement immersed in water or artificial saliva was measured for 2.7 years using an ion selective electrode technique. The RMGIC was affected by water if immersed immediately after setting. This is similar to conventional acid-base cements and the experimental method was designed to allow for this. Over the 2.7-year period, the RMGIC and HD released similar amounts of fluoride into both water and artificial saliva. In water, the RMGIC released the most fluoride, while in artificial saliva the highest release was from HD. KS released the least amount of fluoride in both immersing liquids. In artificial saliva, release was reduced to 17-25% of that found in water, with the RMGIC showing the greatest reduction. Both acid-base cured cements showed changes in colour over the 2.7-year span, while the colour of the RMGIC was stable. It was concluded that the RMGIC released equivalent or greater amounts of fluoride than the two acid-base cure glass-ionomers over a period of 2.7 years.     

Influence of activation modes on diametral tensile strength of dual-curing resin cements

In metallic restorations, the polymerization of dual-curing resin cements depends exclusively on chemical activation. The effect of the lack of photoactivation on the strength of these cements has been rarely studied. This study evaluated the influence of activation modes on the diametral tensile strength (DTS) of dual-curing resin cements. Base and catalyst pastes of Panavia F, Variolink II, Scotchbond Resin Cement, Rely X and Enforce were mixed and inserted into cylindrical metal moulds (4 x 2 mm). Cements were either: 1) not exposed to light (chemical activation = self-cured groups) or 2) photoactivated through mylar strips (chemical and photo-activation = dual-cured groups) (n = 10). After a 24 h storage in 37 masculineC distilled water, specimens were subjected to compressive load in a testing machine. A self-curing resin cement (Cement-It) and a zinc phosphate cement served as controls. Comparative analyses were performed: 1) between the activation modes for each dual-curing resin cement, using Students t test; 2) among the self-cured groups of the dual-curing resin cements and the control groups, using one-way ANOVA and Tukeys test (alpha = 0.05). The dual-cured groups of Scotchbond Resin Cement (53.3 MPa), Variolink II (48.4 MPa) and Rely X (51.6 MPa) showed higher DTS than that of self-cured groups (44.6, 40.4 and 44.5 MPa respectively) (p < 0.05). For Enforce (48.5 and 47.8 MPa) and Panavia F (44.0 and 43.3 MPa), no significant difference was found between the activation modes (p > 0.05). The self-cured groups of all the dual-curing resin cements presented statistically the same DTS as that of Cement-It (44.1 MPa) (p > 0.05), and higher DTS than that of zinc phosphate (4.2 MPa). Scotchbond Resin Cement, Variolink II and Rely X depended on photoactivation to achieve maximum DTS. In the absence of light, all the dual-curing resin cements presented higher DTS than that of zinc phosphate and statistically the same as that of Cement-It (p > 0.05).     

Effect of Alcoholic and Low-pH Soft Drinks on Fluoride Release from Compomer

Purpose: The purpose of this study was to evaluate the amount of fluoride released from compomer restorative materials after immersion in various media. Materials and Methods: In this test, four materials were used: three compomers (Dyract, Dentsply, Konstanz, Germany; Compoglass, Vivadent, Schaan, Principality of Liechtenstein; and Xeno, Sankins, Tochigi, Japan) and one resin‐modified glass ionomer cement (Fuji II LC, GC, Tokyo, Japan). There were four test solutions: one alcoholic (whiskey), two low‐pH drinks (Coca‐Cola, orange juice), and one deionized water. Over a period of 60 days, the tested specimens were immersed in the test solution for 3 hours every day, then kept in deionized water. The fluoride released was detected by using a fluoride ion selective electrode connected to a microprocessor ion analyzer. The fluoride ion concentration (ppm) of the test solutions and deionized water was recorded after 1, 2, 3, 4, 7, 30, and 60 days. Electron probe microanalysis was used for surface analysis of the fluoride released. Results: When immersed in low‐pH soft drinks, compomer showed a significantly higher fluoride release than when immersed in deionized water (p <.0001). For specimens immersed in Coca‐Cola, the fluoride release levels (pg/cm², mean ± SD) at 1, 7, and 60 days for Dyract (91.6 ± 1.8, 39.3 ± 3.1, 10.5 ± 0.9), Compoglass (129.5 ± 0.9, 66.5 ± 2.7, 19.0 ± 0.3), Fuji II LC (147.0 ± 4.2, 50.8 ± 3.1, 27.6 ± 3.0), and Xeno (73.6 ± 3.2, 27.3 ± 2.1, 6.6 ± 0.6) demonstrated the trend of significantly lower releases with time in water solution. Over a 60‐day period, materials immersed in 100% orange juice released the highest amount of fluoride, which could be attributable to the erosive effect of the medium. Materials immersed in deionized water released the least amount of fluoride. Among the tested compomers, Compoglass released the most fluoride. CLINICAL SIGNIFICANCE The results of this study indicate that, at low pH, compomer restorative materials tend to release more fluoride.     

Effect of alcoholic and low-pH soft drinks on fluoride release from compomer

PURPOSE: The purpose of this study was to evaluate the amount of fluoride released from compomer restorative materials after immersion in various media. MATERIALS AND METHODS: In this test, four materials were used: three compomers (Dyract, Dentsply, Konstanz, Germany; Compoglass, Vivadent, Schaan, Principality of Liechtenstein; and Xeno, Sankins, Tochigi, Japan) and one resin-modified glass ionomer cement (Fuji II LC, GC, Tokyo, Japan). There were four test solutions: one alcoholic (whiskey), two low-pH drinks (Coca-Cola, orange juice), and one deionized water. Over a period of 60 days, the tested specimens were immersed in the test solution for 3 hours every day, then kept in deionized water. The fluoride released was detected by using a fluoride ion selective electrode connected to a microprocessor ion analyzer. The fluoride ion concentration (ppm) of the test solutions and deionized water was recorded after 1, 2, 3, 4, 7, 30, and 60 days. Electron probe microanalysis was used for surface analysis of the fluoride released. RESULTS: When immersed in low-pH soft drinks, compomer showed a significantly higher fluoride release than when immersed in deionized water (p < .0001). For specimens immersed in Coca-Cola, the fluoride release levels (microgram/cm2, mean +/- SD) at 1, 7, and 60 days for Dyract (91.6 +/- 1.8, 39.3 +/- 3.1, 10.5 +/- 0.9), Compoglass (129.5 +/- 0.9, 66.5 +/- 2.7, 19.0 +/- 0.3), Fuji II LC (147.0 +/- 4.2, 50.8 +/- 3.1, 27.6 +/- 3.0), and Xeno (73.6 +/- 3.2, 27.3 +/- 2.1, 6.6 +/- 0.6) demonstrated the trend of significantly lower releases with time in water solution. Over a 60-day period, materials immersed in 100% orange juice released the highest amount of fluoride, which could be attributable to the erosive effect of the medium. Materials immersed in deionized water released the least amount of fluoride. Among the tested compomers, Compoglass released the most fluoride.     

Fluoride release from glass-ionomer cements in de-ionized water and artificial saliva

Most of the data reported on the release of fluorides from glass-ionomer cements are based upon measurements made in de-ionized water. De-ionized water does not represent the complex chemistry of the oral environment. In this study, an artificial saliva solution was used, and the data on the fluoride ions released into it from four glass-ionomer cements were compared with those obtained in de-ionized water. The glass-ionomer cements used were: Ketac-Fil (ESPE), Ketac-Silver (ESPE), Fuji-II (GC), and Miracle Mix (GC). Ten disc samples (2 cm x 0.1 cm) of each cement were prepared. Each was individually suspended in either de-ionized water or artificial saliva (five samples in each medium) and stored for 24 h at 37 degrees C, then transferred to fresh media for a total of 60 days. Collected media were buffered with TISAB, and fluoride was measured by a specific electrode. Artificial saliva was prepared according to Fusayama et al. (1963). The data obtained showed that: (1) glass-ionomer cements released more fluoride in de-ionized water than in artificial saliva; (2) Ketac-Fil released 20% more fluoride in saliva than did Fuji-II, the latter releasing 49% more fluoride than Ketac-Fil in de-ionized water; and (3) conventional glass ionomers released more fluoride than did meta-reinforced ones in both media.     

Long-term F release from glass ionomer cements

Fluoride release from three commercial glass ionomer filling cements and three glass ionomer luting cements was measured in the laboratory over a 12-month period. Fluoride release from these glass ionomer cements was compared with that released from a silicate, silicophosphate, and a fluoride-containing polycarboxylate cement. The fluoride released from the glass ionomer cements throughout the one-year period was similar, both in quantity and pattern, to that released by the silicate cement. The silicophosphate cement tended to release fluoride in somewhat lesser amounts, while the amount of fluoride released by the polycarboxylate was negligible after the first few days. Analysis of these data indicates that these glass ionomer cements probably possess anticariogenic properties similar to those of silicate cement.     

Fluoride release from glass ionomer cements and resin composites coated with a dentin adhesive.

OBJECTIVES: This laboratory study compared the effect of surface coatings on patterns and amounts of fluoride released from four glass ionomer cements and two fluoride-containing resin composites. METHODS: Twelve cylinders of each material were prepared in a polyethylene mold. The experimental groups (n = 6) were coated with one layer of an adhesive resin (3M Scotchbond Multipurpose Adhesive), while the control groups (n = 6) remained uncoated. Cumulative fluoride release into deionized water was measured on days 1, 2, 3, 7, 14, 21 and 28 using an ion analyzer. Total fluoride release after 28 days was analyzed for significant differences among materials using one-way ANOVA and Student-Newman-Keuls test (p < 0.05). RESULTS: The total amounts of fluoride release from the coated samples were found to be significantly less than the uncoated samples for all materials, except Solitaire. The uncoated samples released a total amount of fluoride of between 2.3 and 85.4 ppm, while the coated samples released a total amount of fluoride of between < 0.2 and 24.1 ppm. Similar patterns of fluoride release were found in coated and uncoated samples. SIGNIFICANCE: The results indicated that the application of a dentin adhesive coating did not completely prevent fluoride release from glass ionomer cements and fluoridated resin composites, although the amounts were significantly less. Clinically, it suggests that a continued release of fluoride from glass ionomer cements and fluoridated resin composites is possible after placing a thin layer of resin adhesive. The clinical significance of these findings is not known.     

Fluoride release and uptake from glass ionomer cements and composite resins

The aim of this investigation was to evaluate fluoride release and uptake from 4 glass ionomer cements (GICs)--Vitremer (VIT), Fuji II LC (FII LC), Fuji IX (FIX), Chelon Fill (CHE)--and 2 composite resins (CRs)--Heliomolar (H) and Zeta-100 (Z-100). Eight discs (8 mm x 2 mm) were made of each material and were stored in plastic vials containing artificial saliva at 37 degrees C. In group 1 (N = 3), the specimens were immersed in artificial saliva which was changed daily for 25 days. In group 2 (N = 5), besides receiving the same treatment as group 1, the specimens were immersed, after 24 hours, in a fluoride solution (1% NaF) for 1 min before daily saliva change. An ion-specific electrode (9609 BN-Orion) connected to an ion analyzer (SA-720 Procyon) was used to determine the amount of fluoride released at days 1, 2, 5, 10, 15, 20 and 25. Data were analyzed using two way ANOVA and Friedman's test. GICs released more fluoride during the first day and after this period the mean fluoride released decreased. Composite resin H released fluoride during the first day only and Z-100 did not release fluoride. In terms of NaF treatment, CRs did not show fluoride uptake, whereas the GICs showed fluoride uptake (VIT = FII LC = CHE > FIX).