Resin-modified Glass Ionomer Cement Liner Research Articles

To Evaluate Shear Bond Strength of Resin Composite to Theracal Lc, Biodentine, and Resin–Modified Glass Ionomer Cement and Mode of Fracture: An In Vitro Study

Abstract Introduction The aim of the current study was to evaluate shear bond strength of resin composite bonded to Theracal LC, Biodentine, and resin-modified glass ionomer cement (RMGIC) using universal adhesive and mode of fracture. Materials and Methods A total of 50 caries-free maxillary and mandibular molars extracted were taken; occlusal cavities were prepared, mounted in acrylic blocks, and divided into five groups based on the liner used. Group 1: Biodentine liner placed into the cavity and bonding agent and resin composite applied after 12 minutes. Group 2: Biodentine liner placed into the cavity and bonding agent and resin composite applied after 14 days. Group 3: RMGIC liner placed into the cavity and bonding agent and resin composite applied immediately. Group 4: RMGIC liner placed into the cavity and bonding agent and resin composite applied after 7 days. Group 5: Theracal LC liner placed into the cavity and bonding agent and resin composite applied immediately. Each sample was bonded to resin composite using universal adhesive. Shear bond strength analysis was performed at a cross-head speed of 0.1 mm/min. Statistical Analysis Statistical analysis was performed with one-way analysis of variance and posthoc Bonferroni test using SPSS version 22.0. Results and Conclusion Biodentine liner when bonded immediately to resin composite showed minimum shear bond strength. RMGIC when bonded to resin composite after 7 days showed maximum shear bond strength. Mode of fracture was predominantly cohesive in groups having Biodentine and Theracal LC as liner.

The use of a liner under different bulk-fill resin composites: 3D GAP formation analysis by x-ray microcomputed tomography.

Gap formation of composite resin restorations is a serious shortcoming in clinical practice. Polymerization shrinkage stress exceeds the tooth-restoration bond strength, and it causes bacterial infiltration within gaps between cavity walls and the restorative material. Thus, an intermediate liner application with a low elastic modulus has been advised to minimize polymerization shrinkage as well as gap formation.Objective:The purpose of this in vitro study was to assess gap formation volume in premolars restored with different bulk-fill composites, with and without a resin-modified glass-ionomer cement (RMGIC) liner, using x-ray micro-computed tomography (micro-CT).Methodology:Sixty extracted human maxillary premolars were divided into six groups according to bucco-palatal dimensions (n=10). Standardized Class II mesio-occluso-distal cavities were prepared. G-Premio Bond (GC Corp., Japan) was applied in the selective-etch mode. Teeth were restored with high-viscosity (Filtek Bulk Fill, 3M ESPE, USA)-FB, sonic-activated (SonicFill 2, Kerr, USA)-SF and low viscosity (Estelite Bulk Fill Flow, Tokuyama, Japan)-EB bulk-fill composites, with and without a liner (Ionoseal, Voco GmbH, Germany)-L. The specimens were subjected to 10,000 thermocycles (5-55°C) and 50,000 simulated chewing cycles (100 N). Gap formation based on the volume of black spaces at the tooth-restoration interface was quantified in mm3 using micro-computed tomography (SkyScan, Belgium), and analyses were performed. Data were analyzed using repeated-measures ANOVA and the Bonferroni correction test (p < 0.05).Results:The gap volume of all tested bulk-fill composites demonstrated that Group SF (1.581±0.773) had significantly higher values than Group EB (0.717±0.679). Regarding the use of a liner, a significant reduction in gap formation volume was observed only in Group SFL (0.927±0.630) compared with Group SF (1.581±0.773).Conclusion:It can be concluded that different types of bulk-fill composite resins affected gap formation volume. Low-viscosity bulk-fill composites exhibited better adaptation to cavity walls and less gap formation than did sonic-activated bulk-fill composites. The use of an RMGIC liner produced a significant reduction in gap formation volume for sonic-activated bulk-fill composites.

Comparative Evaluation of Effect of Lasers and Biodentine in Dentine Regeneration: A Clinical Study

To compare and evaluate the effect of different liners separately and in combination with lasers that is resin modified glass-ionomer cement (RMGIC), Laser+RMGIC, Biodentine, Laser+Biodentinein the treatment of deep carious lesions. Forty patients with deep caries indicated for pulp capping were selected. Curative procedure including the cavity preparation with maximal removal of softened dentine using spoon excavator, slow speed handpiece with round burs was performed. Patients were divided into four groups with 10 patients in each group In group A RMGIC liner, group B laser biostimulation followed by RMGIC liner, group C biodentine liner, group D laser biostimulation followed by Biodentine liner were placed in the cavity after caries removal. Cavities were temporarily restored with IRM for 8 weeks. After 8 weeks, liners in each group were removed, and cavities were permanently restored lower half of the cavity with a layer of flowable Z350 XT composite, and then the remaining half of the cavity with P60 filled composites (3 M ESPE, USA) in all the groups. The observation period was 12 months. All the patients showed a positive response to cold test and electric pulp test at 3 months, 6 months, 12 months follow-up. In group A (RMGIC) two patients and in group B (Laser+Biodentine) three patients did not return back for the follow-up. To standardize the samples, seven patients were selected from each group with a total of 28 samples included in the study (n = 7) and statistical analysis was done using analysis of variance (ANOVA) test. The mean for the total amount of dentine deposited after 12 months was highest in: Group D-(Laser+Biodenitne) 0.32 mm > Group C-(Biodentine) 0.25 mm > Group B-(Laser+RMGIC) 0.10 > Group A-(RMGIC) 0.07 mm Conclusion: Within the limitation of the present study the following conclusion was drawn: • Lasers and biodentine are good indirect pulp capping agents • Laser has an additional effect on the tertiary dentine formation. Lasers with antibacterial effect penetrate into dentinal tubules and accelerate the rate of dentin bridge formation in deep carious lesions.

Study to evaluate the Efficacy of Resin-modified Glass Ionomer Cement Liner as a Direct Pulp Capping Material

The aim of the present in vivo study was to compare efficacy of light-cured resin-modified glass ionomer liner, Vitrebond™ (3M ESPE) with Dycal® (Dentsply) on the healing of pulpal tissue in the event of a direct iatrogenic pulpal exposure. Experimental group consisted of Vitrebond™ (3M ESPE) resin-modified glass ionomer liner, and Vitremer™ (3M ESPE) resin-modified glass ionomer cement (GIC) in comparison with the control group of Dycal® (Dentsply) as liner and Poly F® (Dentsply) dental cement. Class V cavities were prepared in 32 sound premolars that were scheduled for orthodontic extraction, and the exposures were capped according to groups. Five teeth from each group were extracted under local anesthesia after an interval of 24 hours, 35 and 60 days, and evaluated for inflammation, fibrotic changes, formation of reparative dentin and bacterial examination. The present study did not show any statistically significant difference between two groups in terms of inflammation, fibrosis, reparative dentin formation, and bacterial examination. This study shows that Vitrebond™ (3M ESPE) light-cured resin-modified glass ionomer liner can be used as an alternative to calcium hydroxide as a direct pulp capping material. Light-cured resin-modified glass ionomer liner can be an alternative for the calcium hydroxide-based liner for capping iatrogenic pulp exposures.

Marginal adaptation in proximal cavities restored with composites and other materials

Objective: To evaluate the marginal adaptation, in enamel (E) and dentin (D), of composite resin (CR) associated with flowable resin composite (flow), bulk fill flowable base (bulk) and resin modified glass ionomer cement (RMGIC) in slot cavities. Material and Methods: The study was conducted after approval (Protocol No. 21148413.4.0000.5417) from Ethics Committee. Forty extracted human molar teeth were randomly assigned in eight experimental groups: E-CR, E-BULK, E-FLOW, E-RMGIC, D-CR, D-BULK, D-FLOW, D-RMGIC. The occlusal surface was planned, two slot cavities with standard sizes (depth: 2.0 mm, height: 2.5 mm, width: 2.0 mm) were created on a machine for making cavities. The teeth were restored and after 24h subjected to 2000 cyclic loading and sectioned for analysis of marginal adaptation by scanning electron microscopy (SEM). The micrographs were analyzed with the Image J program to measure the size of marginal gaps. The data were transformed into percentages (%GAPS = LG ÷ LM × 100) and analyzed by 2-way ANOVA followed by the post hoc Tukey test (?=0.05). Results: There was a significant difference between different treatments (p&lt;0.01). The groups E-RMGIC (p=0.001) and D-RMGIC (p=0) had the highest percentage of marginal gap. Others groups showed similar percentage of marginal gap (p&gt;0.05). Conclusions: It was concluded that restorations with flowable composite resin and bulk fill liners exhibit the same behavior, but the RMGIC liner increased marginal gap.Keywords: Composite resins; Dental marginal adaptation; Glass ionomer cements.

Sealing ability of materials used as protective cervical barrier in internal tooth bleaching

The use of a protective cervical barrier (PCB) is very well established to perform a safe internal bleaching; however, there is still no consensus on which material has the best sealing ability. Objective: This in vitro study aimed to evaluate the apical and linear sealing of different PCB materials placed during internalbleaching. Material and methods: This study had two study factors: PCB positioning, divided at two levels (cement-enamel junction [CEJ] and 1mm above the cement enamel junction [CEJ+1]); and PCB material, divided at eight levels (resin composite [RC], glass ionomer cement [GIC], resin-modified glass ionomer cement liner [LRGIC], restorative resin-modified glass ionomer cement [RRGIC], zinc phosphate cement [ZPC], eugenol-free zinc oxide cement [ZOC],provisional filling resin [PFR] and gutta-percha as control [GUT]). Response variables were apical and linear sealing obtained through dye penetration and analyzed with a digital microscope. Data were subjected to two-way analysis of variance followed by Tukey test (p&lt;0.05). Results: The main factor for both apical and linear sealing was the type of material (p&lt;0.01), regardless of their position. RC and ZPC presented the worst sealing values (p&lt;0.05). The Spearmanrank correlation coefficient revealed a positive correlation between the apical and linear leakage. Conclusion: The results suggest that RC and ZPC must be avoided as a PCB during internal bleaching procedures.

Sealing ability of materials used as protective cervical barrier in internal tooth bleaching

The use of a protective cervical barrier (PCB) is very well established to perform a safe internal bleaching; however, there is still no consensus on which material has the best sealing ability. Objective: This in vitro study aimed to evaluate the apical and linear sealing of different PCB materials placed during internal bleaching. Material and methods: This study had two study factors: PCB positioning, divided at two levels (cement-enamel junction [CEJ] and 1mm above the cement enamel junction [CEJ+1]); and PCB material, divided at eight levels (resin composite [RC], glass ionomer cement [GIC], resin-modified glass ionomer cement liner [LRGIC], restorative resin-modified glass ionomer cement [RRGIC], zinc phosphate cement [ZPC], eugenol-free zinc oxide cement [ZOC], provisional filling resin [PFR] and gutta-percha as control [GUT]). Response variables were apical and linear sealing obtained through dye penetration and analyzed with a digital microscope. Data were subjected to two-way analysis of variance followed by Tukey test (p&lt;0.05). Results: The main factor for both apical and linear sealing was the type of material (p&lt;0.01) regardless of their position. RC and ZPC presented the worst sealing values (p&lt;0.05). The Spearman rank correlation coefficient revealed a positive correlation between the apical and linear leakage. Conclusion: The results suggest that RC and ZPC must be avoided as a PCB during internal bleaching procedures.

To evaluate and compare the effect of different light-curing modes and different liners on cuspal deflection in premolar teeth restored with bulk filled or incrementally filled composite measured at different time intervals.

Aim:The aim of this study is to evaluate and to compare the effect of different light-curing modes and different liners on cuspal deflection in premolar teeth restored with bulk filled or incrementally filled composite measured at different time intervals.Materials and Methods:The study was divided into two parts (Part 1-different curing modes, Part 2-different liner) each with sixty extracted human upper premolar teeth with standardized large mesio-occlusal-distal cavities prepared. Each part was divided into two groups according to the composite used (Group A-Filtek Z350 XT, Group B-Sonic fill). Each group was then divided into three subgroups according to the light-curing modes (soft-start, pulse, and continuous curing mode) and liner (Filtek Z350 XT Flowable, Vitremer) used. The cuspal deflection was then measured with a digital micrometer gauge and subjected to statistically analysis using analysis of variance and Tukey's post hoc test.Results:Sonic fill composite, resin-modified glass ionomer cement (RMGIC) liner and curing with soft-start/pulse curing mode had significantly lower cuspal deflection compared to Filtek Z350 XT, flowable liner, and continuous curing mode, respectively.Conclusion:Sonic fill composite, RMGIC liner under the restorations and composites cured with soft start/pulse curing mode resulted in reduced cuspal deflection.

Effect of Lining Materials on Shear Bond Strength for Composite Restorations In Vitro.

This study evaluated the influence of liner agents placed under resin composite restorations on shear bond strength (SBS) to dentin. A total of 40 extracted bovine incisors were used. Enamel surfaces were ground to expose a flat dentin area of 7 mm in diameter. Teeth were divided into four groups according to tested liners: Group 1 (control) used no liner; Group 2 used a resin-modified glass-ionomer cement liner (Vitrebond Plus, 3M ESPE); Group 3 used a light-activated calcium hydroxide resin liner (Ultra-Blend Plus, Ultradent); and Group 4 used a polyacrylic acid surface treatment + conventional glass-ionomer cement liner (Vidrion F, SSWhite). All groups were subjected to bonding procedures with Single Bond (3M ESPE) and 4-mm-thick buildups of resin composite were fabricated. Artificial aging was performed, and the specimens were submitted to mechanical shear testing. One-way analysis of variance (ANOVA) revealed significant differences among liners (P = .00). Group 4 showed the highest SBS. Group 1 showed significantly higher mean SBS compared with Group 3. Results showed that SBS is improved when using polyacrylic acid surface treatment + conventional glass-ionomer cement and decreased when using light-activated calcium hydroxide when compared with no liner. Polyacrylic acid surface treatment + conventional glass-ionomer cement as a liner placed under adhesion surface can improve the shear bond strength between dentin and resin, while light-activated calcium hydroxide resin should be used restrictedly in very deep cavities, because they may reduce the bond strength of the restoration submitted to masticatory forces and temperature changes in the oral environment.

Clinical performance of Class I nanohybrid composite restorations with resin-modified glass-ionomer liner and flowable composite liner: A randomized clinical trial.

Background:Liners play a vital role in minimizing polymerization shrinkage stress by elastic bonding concept and increase the longevity and favorable outcome for composite restorations.Aims:The aim of this study was to evaluate the clinical performance of nanohybrid composite restorations using resin-modified glass-ionomer and flowable composite liners.Settings and Design:A single-centered, double-blinded randomized clinical trial, with split-mouth design and equal allocation ratio that was conducted in the Department of Conservative Dentistry and Endodontics.Materials and Methods:In forty patients, a total of eighty Class I restorations were placed with resin-modified glass-ionomer cement (RMGIC) liner (FUJI II LC, GC America) in one group and flowable composite liner (smart dentin replacement/SDR, Dentsply Caulk, Milford, DE, USA) in another group. All restorations were clinically evaluated by two examiners, immediately (baseline), 3, 6, and 12 months using US Public Health Service modified criteria.Statistical Analysis Used:Statistical analysis was performed using McNemar's test (P < 0.05).Results:There was no significant difference in the color match, marginal discoloration, surface roughness, and marginal adaptation. Restorations with RMGIC liner group show 20% Bravo scores on anatomic form at 12 months but are still clinically acceptable.Conclusion:Nanohybrid composite restorations with RMGIC (Fuji II LC) and flowable composite liner (SDR) demonstrated clinically acceptable performance after 12 months.

Polymerization Shrinkage of Different Types of Composite Resins and Microleakage With and Without Liner in Class II Cavities

To determine the volumetric polymerization shrinkage of four different types of composite resin and to evaluate microleakage of these materials in class II (MOD) cavities with and without a resin-modified glass ionomer cement (RMGIC) liner, in vitro. One hundred twenty-eight extracted human upper premolar teeth were used. After the teeth were divided into eight groups (n=16), standardized MOD cavities were prepared. Then the teeth were restored with different resin composites (Filtek Supreme XT, Filtek P 60, Filtek Silorane, Filtek Z 250) with and without a RMGIC liner (Vitrebond). The restorations were finished and polished after 24 hours. Following thermocycling, the teeth were immersed in 0.5% basic fuchsin for 24 hours, then midsagitally sectioned in a mesiodistal plane and examined for microleakage using a stereomicroscope. The volumetric polymerization shrinkage of materials was measured using a video imaging device (Acuvol, Bisco, Inc). Data were statistically analyzed with Kruskal-Wallis and Mann-Whitney U-tests. All teeth showed microleakage, but placement of RMGIC liner reduced microleakage. No statistically significant differences were found in microleakage between the teeth restored without RMGIC liner (p>0.05). Filtek Silorane showed significantly less volumetric polymerization shrinkage than the methacrylate-based composite resins (p<0.05). The use of RMGIC liner with both silorane- and methacrylate-based composite resin restorations resulted in reduced microleakage. The volumetric polymerization shrinkage was least with the silorane-based composite.

Cuspal Deflection in Premolar Teeth Restored Using Current Composite Resins With and Without Resin-modified Glass Ionomer Liner

To evaluate the effects of four different types of composite resins and a resin modified glass ionomer cement (RMGIC) liner on the cuspal deflection of large MOD cavities in vitro. One hundred twenty-eight extracted human upper premolar teeth were used. After the teeth were divided into eight groups (n=16), standardized large MOD cavities were prepared. The distance between cusp tips was measured before and after the cavity preparations with a digital micrometer. Then the teeth were restored with different resin composites (Filtek Supreme XT, Filtek P60, Filtek Z250, Filtek Silorane - 3M ESPE, St Paul, MN, USA) with and without a RMGIC liner (Vitrebond, 3M ESPE, St Paul, MN, USA). Cuspal deflection was measured 5 min, 24 h, and 48 h after the completion of restorations. The data were statistically analyzed with Friedman and Kruskal Wallis tests. A significant reduction in cuspal deflection was observed in Filtek Silorane restorations with and without RMGIC liner (p<0.05). In all restored teeth, the distance between cusps was reduced but they did not return to their original positions during the 48 h period. All teeth showed cuspal deflection, but placement of RMGIC liner reduced it. The use of silorane-based composites and the placement of RMGIC liner under the composite resin restorations resulted in significantly reduced cuspal deflection.

Evaluation of Microleakage in Class II Cavities using Packable Composite Restorations with and without use of Liners.

The advent of the esthetic era and advances in adhesive technology saw the emergence of resin composite materials. But the problem of polymerization shrinkage remained. This was due to the contraction of the resin during curing inducing internal and interfacial stresses at the tooth restoration interface, leading to gap formation and subsequent micro-leakage. A number of techniques and modifications in the material have been proposed to minimize polymerization shrinkage and microleakage. In this study, the hypothesis that the placement of resin-modified glass ionomer cement (RMGIC) or flowable composite, as liner, beneath the packable composite, on the gingival surface of the tooth [coronal or apical to cementoenamel junction (CEJ)], could reduce the microleakage in class II composite restorations, was tested. Sixty recently extracted noncarious human mandibular molars were used. The teeth were randomly divided into three groups (20 specimens each): Group I (Filtek P60 with RMGIC liner), group II (Filtek P60 with Filtek Z350 liner) and Group III (Filtek P60 without liner). The teeth of each group were further subdivided into two subgroups (equal number of cavities). Subgroup A gingival seat 1 mm occlusal to CEJ on mesial side. Subgroup B gingival seat 1 mm apical to CEJ on distal side. It was concluded that in class II composite restorations gingival microleakage is more at the dentinal surface than on enamel. The use of a flowable composite and RMGIC, as liners, beneath the packable composite, in class II composite restorations, significantly reduces the microleakage when margins are in dentin, but the reverse is true, when the margins are in enamel.How to cite this article: Arora R, Kapur R, Sibal N, Juneja S. Evaluation of Microleakage in Class II Cavities using Packable Composite Restorations with and without use of Liners. Int J Clin Pediatr Dent 2012;5(3):178-184.

In vitro evaluation of microleakage of class II packable composite resin restorations using flowable composite and resin modified glass ionomers as intermediate layers

Aim and Objectives:To evaluate the cervical marginal microleakage of class II packable composite resin restorations using flowable composite and resin modified glass ionomer as intermediate layers and whether the difference in the thickness of these intermediate layers would influence the microleakage.Materials and Methods:Standardized class II box only cavities (4 mm bucco lingual width 2 mm mesio distal depth with the gingival margin 1 mm above the cemento-enamel junction (CEJ) were restored as follows: Group A Restoration with packable composite alone, Group B, Subgroup 1, 1 mm flowable composite liner + packable composite, Sub Group 2, 2 mm flowable composite liner + packable composite, Group C, Subgroup 1, 1 mm resin modified glass ionomer cement (RMGIC) liner + packable composite, Sub Group 2, 2 mm RMGIC liner + packable composite, The specimens were thermocycled, stained with methylene blue, sectioned to evaluate the dye penetration. Data were analyzed using Kruskall Wallis Test and Mann Whitney U test.Results:There was no statistically significant difference between the groups. The difference in the thickness of the intermediate layers did not influence the microleakage.Conclusions:Use of 1 mm of flowable composite intermediate layer improved the sealing ability of packable composites than the differential thickness of resin modified glass ionomer.

Effect of multi-step dentin bonding systems and resin-modified glass ionomer cement liner on marginal quality of dentin-bonded resin composite Class II restorations

The use of resin composites in the restoration of Class II cavities with gingival margins located in dentin is still controversial. The purpose of this in vitro study was to evaluate the effect of four state-of-the-art multi-step dentin-bonding systems (A. R. T. Bond, Syntac, OptiBond DC, Scotchbond Multipurpose) on marginal adaptation and microleakage of dentin-bonded composite Class II restorations. A total of 72 Class II cavities with gingival margins in dentin were prepared in extracted molars and filled with fine-hybrid composites using a three-sited light curing technique. In one half of the cavities the pulpal wall was lined with a resin-modified glass ionomer cement liner (RM-GIC), in the other half a total bonding technique was applied. A. R. T. Bond and Syntac were tested with selective enamel etching (SE) and total etching (TE). Marginal adaptation was evaluated in a scanning electron microscope before and after thermocycling (TC). Microleakage was determined by dye penetration. After TC the proportions of continuous margin in dentin ranged from 37% (Syntac/SE) to 91.2% (A. R. T. Bond/TE). Scotchbond Multipurpose exhibited the lowest degree of microleakage (0.22 mm). Marginal enamel fracture was the most prevalent marginal defect at the enamel margins (8.3-22.2%). The use of the RM-GIC had no beneficial effect on any of the marginal parameters, either in dentin or in enamel. It is concluded that low degrees of marginal gap formation and microleakage can be achieved in totally bonded composite Class II restorations when using state-of-the-art multi-step bonding systems in combination with a meticulous incremental filling technique.

Avaliação in vitro da microinfiltração em cavidades de classe V restauradas com diferentes combinações de resina composta e cimento de ionômero de vidro

O propósito deste estudo foi comparar o padrão de microinfiltração em restaurações classe V usando diferentes combinações de cimento ionomérico/resina composta. Cinqüenta cavidades foram preparadas nas superfícies vestibular e lingual de caninos e de pré-molares recém-extraídos. A margem gengival dos preparos estendeu-se até a dentina/cemento, e a margem oclusal localizou-se em esmalte. As cavidades foram restauradas como se segue: cimentos ionoméricos restauradores modificados por componentes resinosos (Fuji II LC e Vitremer); sistema adesivo/resina composta (Scotchbond Multi-Uso/Silux Plus); técnica sanduíche empregando-se o sistema adesivo/resina composta descrito, com um cimento ionomérico forrador (Vitrebond e GC Lining LC). Os espécimes foram armazenados em água destilada, polidos, submetidos à ciclagem térmica e imersos em fucsina. A extensão de penetração do corante foi classificada segundo o critério de escores, e os dados foram analisados estatisticamente, não sendo observadas diferenças significativas tanto entre materiais como entre margens.