|Year : 2019 | Volume
| Issue : 7 | Page : 961-970
The evaluation of microleakage and fluoride release of different types of glass ionomer cements
E Bahsi1, S Sagmak1, B Dayi2, O Cellik3, Z Akkus4
1 Department of Restorative Dentistry, Dicle University, Faculty of Dentistry, Diyarbakir, Turkey
2 Department of Restorative Dentistry, Inonu University, Faculty of Dentistry, Malatya, Turkey
3 Department of Restorative Dentistry, Faculty of Dentistry, Adiyaman University, Adiyaman, Turkey
4 Department of Biostatistics, Dicle University, Faculty of Medicine, Diyarbakir, Turkey
|Date of Acceptance||22-Feb-2019|
|Date of Web Publication||11-Jul-2019|
Dr. E Bahsi
Department of Restorative Dentistry, Dicle University, Faculty of Dentistry, Diyarbakir - 21280
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Background: The aim of this study was to evaluate six different glass ionomer cement (GIC)-based restorative materials through comparisons of microleakage and fluoride release. Materials and Methods: For microleakage, 30 teeth were randomly separated into 6 groups of 5: Group 1 (Dyract: compomer), Group 2 (Freedom: compomer), Group 3 (Equia: high-viscosity glass ionomer cements), Group 4 (Fuji IX: resin-modified glass ionomer cement), Group 5 (Ketac Molar: traditional glass ionomer cement [TGIC]) and Group 6 (Voco: TGIC). For fluoride release of six different GIC-based restorative materials, standard samples were prepared of 4 mm thickness and 7 mm diameter. A total of 60 samples were obtained as 10 samples from each group. The analyses were made using a Thermo Orion 720 A+ ionometer with the Orion fluoride electrode. At the end of 24 h, 72 h, 7 days, 14 days, and 30 days, the electrode was placed into the dish containing the sample, distilled water, and TISAB II; a reading was taken; and the value shown on the screen was recorded. Results: For microleakage, a statistically significant difference was determined between the groups in respect of the occlusal variable (P < 0.05), no statistically significant gingival variable (P > 0.05). About fluoride release: According to the repeated measures variance analysis results, the difference between the groups, and between the time-group interaction and according to time, was found to be statistically significant (P < 0.05). Conclusions: In terms of microleakage, it was concluded that all materials could be used in clinical applications. The Equia high-viscosity glass ionomer cements (HVGIC) was determined to be the material with the highest fluoride release value.
Keywords: Fluoride release, glass ionomer cement, microleakage
|How to cite this article:|
Bahsi E, Sagmak S, Dayi B, Cellik O, Akkus Z. The evaluation of microleakage and fluoride release of different types of glass ionomer cements. Niger J Clin Pract 2019;22:961-70
|How to cite this URL:|
Bahsi E, Sagmak S, Dayi B, Cellik O, Akkus Z. The evaluation of microleakage and fluoride release of different types of glass ionomer cements. Niger J Clin Pract [serial online] 2019 [cited 2019 Jul 22];22:961-70. Available from: http://www.njcponline.com/text.asp?2019/22/7/961/262533
| Introduction|| |
Protective and preventative procedures with the preservation of healthy dental tissue are at the forefront of modern dentistry practices. For the provision and protection of the integrity of dental hard tissues, direct restorative applications that can be applied in a single session have become more preferred.
Amalgam, composite resin, and glass ionomer cements (GICs) are used in routine clinical applications as permanent direct restorative materials.
GICs were first developed by Wilson and Kent in 1972 and were introduced under the name ASPA (alumino-silicate-polyacrylic acid). GICs obtained from a mixture of powder and liquid forms were defined as hybrids of polycarboxylate cement with silicate cement.
The physical properties developed depending on changes in the chemical content and powder-liquid ratios of GICs have provided more extensive areas of use in clinical applications., The anticariogenic potential related to fluoride release, biocompatibility, and chemical adaptation to dental tissues have rendered GICs a special material group. However, weak mechanical properties such as low resistance to fracture, hardness, and resistance to wear limit its use as a restorative material in the posterior regions that are exposed to intense stress.,
The content of GICs can be classified under five headings:
- Traditional glass ionomer cements (TGICs)
- Hybrid glass ionomer cements
- Resin-modified glass ionomer cements (RMGICs)
- Polyacid-modified composite resins (compomers)
One of the most important factors affecting the clinical success of cervical region restorations is marginal leakage, which is defined as the microscopic passage of bacteria, fluid molecules, and ions between the restoration and dental tissues. Several negative conditions can be encountered as a result of microleakage, including postoperative sensitivity, marginal discoloration, impaired marginal integrity, and secondary caries. There are two basic reasons for the formation of microleakage in cervical region restorations. These are that moisture control is difficult during the application because of the proximity of the lesions to the gingiva and that functional forces create stress on the tooth in the cervical region.
The borders of restorations in the cervical region usually include enamel, dentin and cement, and any deficiency of the restorative material which can be strongly bound at the same degree to each of the three tissues makes restorations to be applied in the cervical region more difficult. The other problems encountered in servical region are; polymerization shrinkage, the reduction of bonding due to the progression of dentin tubules, and the formation of micro gaps between the tooth-restoration because of thermal changes in the mouth. Marginal compatibility between the cavity and restorative material is of critical importance for the long-term performance of restorations to be able to be maintained.
To increase the resistance of dental structures to caries, fluoride and materials containing fluoride are currently often selected. The basic effect of fluoride in strengthening dental structures is provided by the transformation of hydroxyapatite crystals to fluoroapatite crystals that are more resistant to acid. Fluoride also has a bactericide and bacteriostatic effect on the glycose transport systems of microorganisms and carbohydrate metabolism. Just as fluoride can be used in the form of a preparate, it can also be added to amalgam, composites, compomers, adhesive systems, GIC, and RMGIC. Previous studies have shown that glass ionomer-based materials are superior to other materials in respect of fluoride release.
Silver ions are used to increase the antibacterial efficacy of materials. Previous studies have demonstrated that the addition of silver to the content of composite resin and GIC increased the efficacy. The main disadvantage of adding silver is that it destabilizes the color of the material.
The aim of this study was to evaluate six different GIC-based restorative materials through comparisons of microleakage and fluoride release. The materials used were two different TGIC, two different RMGIC, and two different compomers.
| Materials and Methods|| |
This study was planned in two stages. In the first stage, the materials were evaluated in respect of microleakage, and in the second stage in respect of fluoride release.
At the microleakage stage, 30 newly extracted, permanent human molar teeth without cavities were used. After extraction, remnant tissues were removed from the root surfaces with a curette, and the teeth were kept in distilled water at 37°C. Standard class V cavities were made of mesiodistal width 3 mm, cervico-occlusal width 2 mm, and depth 1.5 mm, with a cylindrical diamond bur under water cooling to all teeth by a single researcher. Gingival margins were extended to 1 mm below the enamel–cement border. Beveling was not applied to the cavity edges. The teeth were randomly separated into six groups of five.
Group 1 (Dyract: compomer)
Orthophosphoric acid 37% was applied to the cavities for 30 s to the enamel and 15 s to the dentin. The cavities were washed with an air–water spray and then dried. The bonding agent (Bond Force II, Tokuyama Dental Corp., Japan) was spread in the cavity with light air and was then polymerized with an LED light source for 10 s. Compomer (Dyract XP, Dentsply DeTrey, Konstanz, Germany) was placed in the cavity in layers of up to 2 mm thickness and each layer was polymerized with a LED light source for 20 s.
Group 2 (Freedom: compomer)
Orthophosphoric acid 37% was applied to the cavities for 30 s to the enamel and 15 s to the dentin. The cavities were washed with an air–water spray and then dried. The bonding agent (Bond Force II, Tokuyama Dental Corp., Japan) was spread in the cavity with light air and was then polymerized with an LED light source for 10 s. Compomer (Freedom, SDI Limited Bayswater, Australia) was placed in the cavity in layers of up to 2 mm thickness and each layer was polymerized with a LED light source for 20 s.
Group 3 (Equia Fil: RMGIC)
The cavities were washed with water and gently dried with air. The prepared surfaces should appear damp. To prepare the RMGIC (Equia Fil, GC Dental, Tokyo, Japan) capsule for use, it was first shaken and the lower part was pushed as far as the capsule body. The capsule was quickly placed into a capsule gun and by pressing the arm once, the mixture was made ready for use. The capsule was immediately placed into an amalgamator and mixed at high speed (±4000 rpm) for 10 s. The capsule was then inserted into the applicator gun and was injected into the cavity. The working time from the start of the mixing procedure was 1 min 15 s. The greatest care was taken against moisture contamination throughout the first 2 min 30 s.
Group 4 (Fuji IX: RMGIC)
The cavities were washed with water and gently dried with a cotton wool pellet and air. To prepare the RMGIC (Fuji IX, GC Dental, Tokyo, Japan) capsule for use, it was first shaken and the button was completely pushed as far as the capsule body. The capsule was quickly placed into a capsule gun and by pressing the trigger once, the mixture was made ready for use. The capsule was immediately placed into an amalgamator and mixed at high speed (±4000 rpm) for 10 s. The capsule was then inserted into the applicator gun and was injected into the cavity. The working time from the start of the mixing procedure was 2 min. The starting contour was shaped. The polymerization period was 6 min, after which the restoration was finished with standard techniques.
Group 5 (Ketac Molar: TGIC)
The cavities were washed and gently dried, avoiding over-drying. The ratio of the mixture of the TGIC (Ketac Molar Easymix, 3M ESPE, Germany) should be 4.5 unit of powder (1 spoonful) to 1 unit of liquid (1 drop). The powder was divided into two parts and mixed with the liquid to create a homogenous structure. The material should not be mixed for more than 30 s. The homogenous mixture was applied to the cavity in layers. The working time together with the mixing was 3 min and the polymerization time was 5 min. During the hardening process, the material is sensitive to moisture and should be insulated with varnish. After polymerization, the restoration was finished using an Arkansas stone, fine-grained diamond cutter.
Group 6 (Voco: TGIC)
The cavities were washed with water and dried with air. A measure of powder from the TGIC (Ionofil, Voco, GmbH, Germany) was mixed with 1 drop of liquid. The powder: liquid ratio was 4:1. A metal or plastic spatula should be used for the mixing process. The liquid is added to half the powder and mixed; then, the other half of the powder is added and mixed. The mixing time was 50–60 s and the working time should not exceed 1–2 min. The polymerization after the mixing time was 4–5 min. During the polymerization process, the material is sensitive to moisture and should be insulated with varnish. After polymerization, the restoration was finished using an Arkansas stone, fine-grained diamond cutter.
At 24 h after the restorations, the finishing and polishing procedures were applied to all the teeth in all the experimental groups using aluminum oxide-coated disks (Sof-Lex, 3M ESPE, St. Paul, MN, USA). Then, the samples were incubated for 24 h at 37°C. At the end of this period, 1000 thermal cycles were applied to the teeth at 30 s, each of 5 ± 2°C–55 ± 2°C. Then, two coats of clear nail varnish were applied to the whole outer surface leaving a 1-mm gap at the restoration edges. After the varnish dried, the teeth were left in 0.5% basic fuchsin for 24 h, then removed and washed under running water. The teeth were separated into two equal parts in the buccolingual direction passing through the center of the restoration, and thus, 10 samples were obtained for each group. Stain leakage at the restoration edges was examined in all the samples by the same researcher using a stereomicroscope (Leica Z16 APO, Germany) at ×57 magnification. Stain leakage in the cavity walls in the interface between the tooth and the restoration was scored as shown below:
- Score 0: no stain leakage
- Score 1: 0–1 mm stain leakage
- Score 2: 1–2 mm stain leakage
- Score 3: >2 mm stain leakage.
The gingival and occlusal microleakage scores are shown in [Table 1].
The scores obtained from the samples were evaluated statistically. Then, one sample was randomly selected from each group and SEM images were obtained at three different magnifications [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6].
|Figure 1: (a-c) The SEM images of Group Dyract from 500 to 5000. (a) Dyract ×500. (b) Dyract ×2500. (c) Dyract ×5000|
Click here to view
|Figure 2: (a-c) The SEM images of Group Equia from 500 to 5000. (a) Equia ×500. (b) Equia ×2500. (c) Equia ×5000|
Click here to view
|Figure 3: (a-c) The SEM images of Group Freedom from 500 to 5000. (a) Freedom ×500. (b) Freedom ×2500. (c) Freedom ×5000|
Click here to view
|Figure 4: (a-c) The SEM images of Group Fuji IX from 500 to 5000. (a) Fuji ×500. (b) Fuji ×2500. (c) Fuji ×5000|
Click here to view
|Figure 5: (a-c) The SEM images of Group Ketac Molar from 500 to 5000. (a) Ketac Molar ×500. (b) Ketac Molar ×2500. (c)s Ketac Molar ×5000|
Click here to view
|Figure 6: (a-c) The SEM images of Group Voco from 500 to 5000. (a) Voco ×500. (b) Voco ×2500. (c) Voco ×5000|
Click here to view
Fluoride release: Ion selective electrode test
To examine the fluoride release of six different GIC-based restorative materials, standard samples were prepared of 4 mm thickness and 7 mm diameter. A total of 60 samples were obtained as 10 samples from each group. When preparing the samples for analysis at the microleakage stage, the manufacturer's instructions were followed. The analyses were made using a Thermo Orion 720 A+ ionometer with the Orion fluoride electrode (9609 BNWP), which was filled with special filling solution (Orion ion plus filling solution – 900061), and the 0.1-M F standard (Orion ion plus application solution – 940906) produced by Orion (standard methods 2005, 21st ed., 4550F-C).
In the fluoride ion analysis with the electrode, TISAB II solution (Orion ion plus application solution – 940909) was used as a buffer to prevent intervention. The TISAB II buffer solution was prepared in the standard manner and used in the ratio of 1:1 at the sample analysis stage. Before each assay, the electrode was calibrated, and the accuracy of the calibration was checked during the assay, with recalibration applied as necessary. For the calibration of the electrode, four calibration standards were used (1–10–50–100 ppm) related to the concentration range to be studied. Each sample was weighed on sensitive scales and the weight was recorded; then 5 ml TISAB II was added to 5 ml distilled water over the sample, which was then incubated at 37°C.
At the end of 24 h, 72 h, 7 days, 14 days, and 30 days, the electrode was placed into the dish containing the sample, distilled water, and TISAB II; a reading was taken; and the value shown on the screen was recorded. Three measurements were taken from each sample at each time point and the average of the three measurements was used for the analysis. Before and after each measurement, the tip of the electrode was washed in distilled water and lightly dried to remove any remaining fluoride ions.
| Results|| |
The statistical analyses of the study were applied in two stages.
Statistical analyses of the data were made using SPSS 20.0 software. Conformity of the data to normal distribution was evaluated using the Shapiro–Wilk test. As the data did not show normal distribution, comparisons between the groups were made using the nonparametric Kruskal–Wallis variance analysis. A statistically significant difference was determined between the groups in respect of the occlusal variable (P < 0.05).
As no statistically significant difference was determined between the groups in respect of the gingival variable, multiple comparisons were not made (P > 0.05).
As a statistically significant difference was determined between the groups in respect of the occlusal variable, paired comparisons were made between the groups using the post hoc Bonferroni-corrected Mann–Whitney U test. According to these results, no statistically significant difference was found between groups 1–2, 1–3, 1–4, 1–5, 1–6, 2–3, 2–4, 2–5, 2–6, 3–4, 3–5, 3–6, 4–5, 4–6, and 5–6 (P > 0.05).
As the data showed normal distribution in the Shapiro–Wilk test of normality, comparisons of the groups according to time were made using the repeated measurements two-way variance analysis method (repeated measures ANOVA).
Before comparisons of the data, first assessment was made of a sufficient number of samples and multivariable normal distribution. The mean and standard deviation values and number of samples of the groups are shown in [Table 2]. For all the values (as assumptions of homogeneity were not met), multivariate analyses were used as the groups were not seen to be homogenous according to the Box M variance homogeneity test and paired comparisons were made with the application of the Tukey honestly significant difference (HSD), Bonferroni test, and the Bonferroni-corrected paired samples t-test. Groups showing a difference were identified. The paired comparisons of groups and times are shown in [Table 3]. According to the repeated measures variance analysis results, the difference between the groups, and between the time-group interaction and according to time, was found to be statistically significant (P < 0.05).
|Table 3: Binary comparisons of groups and times, standard deviations, and P values|
Click here to view
| Discussion|| |
The currently increasing aesthetic demands of dental patients have played a significant role in the development of materials used for restorative purposes. Problems such as the aesthetic appearance of materials, resistance to occlusal forces, and resistance to wear have been significantly reduced with these developments. Despite all these positive developments, the formation of microleakage at the restoration edges remains an extremely important problem. Microleakage has been reported to be one of the most significant reasons for aesthetic loss in existing restorations and even the emergence of pathological states in the pulp.
For successful restoration of a tooth, there should be sufficient enamel and dentin margins of nonleakage in the restorative material. The presence of a chemical bond, marginal integrity, stability, and adhesiveness of the bond play an important role in the lifespan of the tooth structure. In this study, microleakage of six types of glass ionomer restoration placed in Class V cavities was examined using the stain penetration test. Microleakage is an important characteristic in the evaluation of any restorative material used in dental restorations.
To determine microleakage in restorations, SEM studies, thermal and mechanical cycles, staining such as 0.5–2% basic fuchsin, 50% silver nitrate, and 0.2–2% methylene blue, and various methods have been of benefit for many years. As the oldest method used in leakage studies, organic staining is preferred much more than other methods as it is simple and cheap. In the current study, the simple and widely used method of 0.5% basic fuchsin was used, as it is one of the most preferred staining solutions.
There is current consensus that no material and technique can completely eliminate microleakage, and it has been reported that more leakage is seen from the gingival margins in the dentin–cement junction line of cervical lesions than from the occlusal margins in the enamel., In the current study, the occlusal microleakage scores were found to be more successful than the gingival microleakage scores.
In a study by Balgi et al., microleakage was examined in SDI Riva Self Cure GIC and GC Fuji IX GP EXTRA materials left in sugar cane juice, chocolate milk, and mango drink, and no statistically significant difference was determined.
Ayna et al. examined the microleakage of dye at the edges of primary-teeth restorations using three glass ionomer-based restorative materials (Group A: Ketac Molar, Group B: Photac Fil and Group C: Dyract XP). At the end of the study, they said, polyacid-modified composite resin (compomer) may be a useful restorative material in primary teeth in terms of minimizing microleakage.
In a study by Pontes et al., they evaluate in vitro the marginal microleakage of conventional GICs and RMGICs. They prepared 80 class V cavities (2.0 × 2.0 mm) in bovine incisors, either in the buccal face. The results of the study showed that there was no difference between the enamel and dentin margins. However, GIC materials presented more microleakage than RMGIC.
Shruthi et al. evaluated TGIC, RMGIC, and compomer materials in respect of microleakage and reported that there was no difference.
Following conventional and chemomechanical removal from caries, the microleakage of traditional and resin-modified GIC was examined in a study by Pavuluri et al., and no statistically significant difference was determined.
In the current study, evaluation of microleakage was made of two different TGIC, two different RMGIC, and two different compomers, and no statistically significant difference was determined between them. The most successful was TGIC followed by compomer and the least successful was RMGIC.
One of the positive characteristics of GICs which makes them preferable as restorative materials is the capacity to release fluoride. Fluoride release of a material is important in respect of the anticariogenic property. Continuous fluoride release by GICs prevents the formation of secondary caries.,
It is accepted that TGICs are effective in the prevention of caries because of the property of long-term fluoride release. High fluoride release in the first 24 h reacting with polyalchenoic acid of glass particles during the polymerization reaction results in a “burst effect.” The high fluoride release initially seen rapidly decreases after 24–72 h, approaches a stable level within 10–20 days, and the fluoride in the cement content is used up extremely quickly within a few months.,
The drop in fluoride release over time reduces the ability of the material to prevent the formation of secondary caries, because fluoride released at low doses is not sufficient for a protective effect against caries. However, TGIC has the capacity to be able to take fluoride from the surroundings depending on the concentration gradient. Therefore, these cements are accepted as a fluoride depot. The two different TGICs used in the current study showed maximum fluoride release in the first 24 h and this release gradually reduced and reached the fourth week.
RMGIC generally has as much fluoride release potential as TGIC. However, fluoride release is not only fluoride components and their interaction with polyacrylic acid but the contents for the photochemcal polymerization reaction are also affected by the resin type and amount. In some studies in literature, while the most fluoride release has been observed in RMGIC, the least has been found in compomers. Several studies have shown that the highest release is in the first 24 h and the fluoride release from the material has rapidly fallen to a stable level.,, In the current study, the RMGICs were found to be more successful than compomers in respect of fluoride release.
Rothwell et al. examined fluoride release before and after the application of a toothpaste of TGIC, 2 RMGICs, and a compomer. According to the results of that study, the most fluoride release was observed in the RMGICs. Although the fluoride release of all the materials increased after the application of the toothpaste, it fell again to the initial level within 3 days. Selimovic-Dragas et al. compared the fluoride release of TGIC and RMGICs and the fluoride release of the RMGICs was reported to be higher than that of TGIC at all the measured times.
Malik et al. found out the amount of fluoride release from GIC-containing fluoroapatite and hydroxyapatite. As a result of their study, it is concluded that addition of fluoroapatite into GIC has significant effect on the amount of fluoride release as compared to GIC alone; however, addition of hydroxyapatite into GIC has no additive effect on the amount of fluoride release.
Garoushi et al. evaluated and compared 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). At the end of research, they reported that highest fluoride-release measurement was located for GC Fuji II LC among other tested materials.
In a study by Kucukyilmaz et al., they evaluate the microtensile bond strength of different GICs on sound/caries-affected dentin and to assess the fluoride release/recharging ability. They used Ketac N100, GC Equia, and GCP Glass Fill materials. The results of the study showed that high-viscosity GICs show higher initial fluoride release as well as greater fluoride recharge capacity.
| Conclusions|| |
The data obtained in this study demonstrated that in the evaluations of microleakage of RMGIC, TGIC, and compomers, there was no significant superiority of any of the materials over the others, and thus, it was concluded that all could be used in clinical applications.
All the materials in the study were observed to release fluoride at all the test periods. The Equia RMGIC was determined to be the material with the highest fluoride release value. The RMGICs showed a higher fluoride release value than both compomers and TGICs at all the measured times. The fluoride release values were from highest to lowest in RMGIC, TGIC, and then compomers.
There is a need for further clinical studies to confirm the data obtained in vitro studies related to microleakage and fluoride release.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Hickel R, Manhart J, Garcia-Godoy F. Clinical results and new developments of direct posterior restorations. Am J Dent 2000;13:41-54.
Wilson AD, Kent BE. A new translucent cement for dentistry. The glass ionomer cement. Br Dent J 1972;132:133-5.
Koroglu A, Ekren O, Kurtoglu C. Conventional and adhesive dental luting agents; a literature review. J Dent Fac Ataturk Uni 2012;22:205-16.
Torabzadeh H, Ghasemi A, Shakeri S, Baghban AA, Razmavar S. Effect of powder/liquid ratio of glass ionomer cements on flexural and shear bond strengths to dentin. Braz J Oral Sci 2011;10:204-7.
Nicholson JW. Review: Glass ionomer dental cements: Update. Mater Tech 2010;25:8-13.
Xie D, Brantley WA, Culbertson BM, Wang G. Mechanical properties and microstructures of glass-ionomer cements. Dent Mater 2000;16:129-38.
Kanik O, Turkun S. Recent approaches in restorative glass ionomer cements. J Dent Ege Uni 2016;37:54-65.
Nguyen C. A New in vitro
Method for the Study of Micro-Leakage of Dental Restorative Materials [thesis]. Adelaide: The University of Adelaide; 2007.
Larson TD. The clinical significance of marginal fit. Northwest Dent 2012;91:22-9.
Dayangac GB. Composite Resin Restorations. Ankara, Gunes Kitapevi Company; 2000. p. 1-99.
Eliguzeloglu E, Uctasli MB, Omurlu H, Atesagaoglu A. The effecst of different types of adhesive systems on the microleakage of class V compomer restorations. J Dent Gazi Uni 2006;23:71-7.
Hengtrakool C, Pearson GJ, Wilson M. Interaction between GIC and S. sanguis biofilms: Antibacterial properties and changes of surface hardness. J Dent 2006;34:588-97.
Imazato S. Antibacterial properties of resin composites and dentin bonding systems. Dent Mater 2003;19:449-57.
Gupta PK, Garg G, Kalita C, Saikia A, Srinivasa TS, Satish G. Evaluation of sealing ability of biodentine as retrograde filling material by using two different manipulation methods: An in vitro
study. J Int Oral Health 2015;77:111-4.
Larson TD. The clinical significance and management of microleakage. Part two. Northwest Dent 2005;84:15-9.
Mitra SB, Lee CY, Bui HT, Tantbirojn D, Rusin RP. Long-term adhesion and mechanism of bonding of a paste-liquid resin-modified glass-ionomer. Dent Mater 2009;25:459-66.
Mali P, Deshpande S, Singh A. Microleakage of restorative materials: An in vitro
study. J Indian Soc Pedod Prev Dent 2006;24:15-8.
] [Full text]
Dalli M, Sahbaz C, Bahsi E, Ince B, Colak H, Zorba, YO, et al
. The effects of disinfectants on microleakage in Class V cavity:In vitro
studies. J Dent Fac Ataturk Uni 2009;19:14-9.
Santini A, Ivanovic V, Ibbetson R, Milia E. Influence of marginal bevels on microleakage around Class V cavities bonded with seven self etching agents. Am J Dent 2004;17:257-61.
Celik C, Yazici AR, Dayangac B, Ozgunaltay G. Effect of two different light curing units on microleakage of flowable restorative materials. J Dent Fac Hacettepe Uni 2007;31:64-70.
Balgi P, Katge F, Pradhan D, Shetty S, Rusawat B, Pol S. Comparative evaluation of micro-leakage of two newer glass ionomer cements in primary molars immersed in three beverages:In vitro
study. Ceylon Med J 2017;62:184-8.
Ayna B, Celenk S, Atas O, Tümen EC, Uysal E, Toptanci IR. Microleakage of glass ionomer based restorative materials in primary teeth: An in vitro
study. Niger J Clin Pract 2018;21:1034-7.
] [Full text]
Pontes DG, Guedes-Neto MV, Cabral MF, Cohen-Carneiro F. Microleakage evaluation of class V restorations with conventional and resin-modified glass ionomer cements. Oral Health Dent Manag 2014;13:642-6.
Shruthi AS, Nagaveni NB, Poornima P, Selvamani M, Madhushankari GS, Subba Reddy VV. Comparative evaluation of microleakage of conventional and modifications of glass ionomer cement in primary teeth: An in vitro
study. J Indian Soc Pedod Prev Dent 2015;33:279-84.
] [Full text]
Pavuluri C, Nuvvula S, Kamatham RL, Nirmala S. Comparative evaluation of microleakage in conventional and RMGIC restorations following conventional and chemomechanical caries removal: An in vitro
study. Int J Clin Pediatr Dent 2014;7:172-5.
Gao W, Smales RJ, Yip NK. Demineralisation and remineralisation of dentine caries, and the role of glassionomer cements. Int Dent J 2000;50:51-6.
Nicks MJ, Flaitz CM. Resin-modified glass-ionomer restorations and in vitro
secondary caries formation in coronal enamel. Quintessence Int 2000;31:570-8.
Moshaverinia A, Chee WW, Brantley WA, Schricker SR. Surface properties and bond strength measurements of N-vinylcaprolactam (NVC)-containing glass-ionomer cements. J Prosthet Dent 2011;105:185-93.
Moshaverinia A, Rohpour N, Billington RW, Darr JA, Rehman IU. Synthesis of N-vnylpyrrolidone modified acrylic acid copdymer in supercritical fluids and its application in dental glass-ionomer cements. J Mater Sci Mater Med 2008;19:2705-11.
Wiegand 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;23:343-62.
Sidhu SK. Glass-ionomer cement restorative materials: A sticky subject. Aust Dent J 2011;56(Suppl 1):23-30.
Arbabzadeh-Zavareh F, Gibbs T, Meyers IA, Bouzari M, Mortazavi S, Walsh LJ. Recharge pattern of contemporary glass ionomer restoratives. Dent Res J (Isfahan) 2012;9:139-45.
Tjandrawinata R, Irie M, Suzuki K. Marginal gap formation and fluoride release of resin-modified glass-ionomer cement: Effect of silanized spherical silica filler addition. Dent Mater J 2004;23:305-13.
Khoroushi M, Keshani F. A review of glass-ionomers: From conventional glass-ionomer to bioactive glass-ionomer. Dent Res J (Isfahan) 2013;10:411-20.
Nagaraja Upadhya P, Kishore G. Glass ionomer cement – The different generations. Trends Biomater Artif Organs 2005;18:158-65.
Selimović-Dragaš M, Hasić-Branković L, Korać F, Đapo N, Huseinbegović A, Kobašlija S, et al
. In vitro
fluoride release from a different kind of conventional and resin modified glass-ionomer cements. Bosn J Basic Med Sci 2013;13:197-202.
Rothwell M, Anstice HM, Pearson GJ. The fluoride uptake and release of fluoride by ion-leaching cements after exposure to toothpaste. J Dent 1998;26:591-7.
Malik S, Ahmed MA, Choudhry Z, Mughal N, Amin M, Lone MA. Fluoride release from glass ionomer cement containing fluoroapatite and hydroxyapatite. J Ayub Med Coll Abbottabad 2018;30:198-202.
Garoushi S, Vallittu PK, Lassila L. Characterization of fluoride releasing restorative dental materials. Dent Mater J 2018;37:293-300.
Kucukyilmaz E, Savas S, Kavrik F, Yasa B, Botsali MS. Fluoride release/recharging ability and bond strength of glass ionomer cements to sound and caries-affected dentin. Niger J Clin Pract 2017;20:226-34.
] [Full text]
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]
[Table 1], [Table 2], [Table 3]