Effect of light-activation methods and water storage on the flexural strength of two composite resins and a compomer

The present study evaluated the flexural strength of three composite resins recommended for direct esthetic restorations: a polyacid modified composite (Dyract AP), a unimodal composite resin (Filtek Z250) and a hybrid composite resin (Point 4). The variation factors, apart from the type of composite resin, were the light activation method and the water storage period. The composite resins were light-cured in continuous mode (40 s, 500 mW/cm²) or in ramp mode (0-800 mW/cm² for 10 s followed by 30 s at 800 mW/cm²) and stored for 24 hours or 30 days in distilled water at 37°C. The data were analyzed by ANOVA and Tukey test for multiple comparisons (alpha = 0.05). The composite resin Z250 presented the highest mean flexural strength (166.74 MPa) and Dyract AP presented the lowest one (129.76 MPa). The storage for 30 days decreased the flexural strength in ramp mode (24 h: 156.64 MPa; 30 days: 135.58 MPa). The light activation method alone did not lead to different flexural strength values.

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Influence of Hydrogen Peroxide Bleaching Gels on Color, Opacity, and Fluorescence of Composite Resins

Operative Dentistry ◽

10.2341/11-189-l ◽

2012 ◽

Vol 37 (5) ◽

pp. 526-531 ◽

Cited By ~ 10

Author(s):

CRG Torres ◽

CF Ribeiro ◽

E Bresciani ◽

AB Borges

Keyword(s):

Hydrogen Peroxide ◽

Composite Resin ◽

Color Change ◽

Composite Resins ◽

Control Group ◽

Peroxide Bleaching ◽

Color Changes ◽

Tukey Test ◽

Bleaching Gels ◽

Bleaching Treatment

SUMMARY The aim of the present study was to evaluate the effect of 20% and 35% hydrogen peroxide bleaching gels on the color, opacity, and fluorescence of composite resins. Seven composite resin brands were tested and 30 specimens, 3-mm in diameter and 2-mm thick, of each material were fabricated, for a total of 210 specimens. The specimens of each tested material were divided into three subgroups (n=10) according to the bleaching therapy tested: 20% hydrogen peroxide gel, 35% hydroxide peroxide gel, and the control group. The baseline color, opacity, and fluorescence were assessed by spectrophotometry. Four 30-minute bleaching gel applications, two hours in total, were performed. The control group did not receive bleaching treatment and was stored in deionized water. Final assessments were performed, and data were analyzed by two-way analysis of variance and Tukey tests (p<0.05). Color changes were significant for different tested bleaching therapies (p<0.0001), with the greatest color change observed for 35% hydrogen peroxide gel. No difference in opacity was detected for all analyzed parameters. Fluorescence changes were influenced by composite resin brand (p<0.0001) and bleaching therapy (p=0.0016) used. No significant differences in fluorescence between different bleaching gel concentrations were detected by Tukey test. The greatest fluorescence alteration was detected on the brand Z350. It was concluded that 35% hydrogen peroxide bleaching gel generated the greatest color change among all evaluated materials. No statistical opacity changes were detected for all tested variables, and significant fluorescence changes were dependent on the material and bleaching therapy, regardless of the gel concentration.

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Effect of light sources and curing mode techniques on sorption, solubility and biaxial flexural strength of a composite resin

Journal of Applied Oral Science ◽

10.1590/s1678-77572012000200021 ◽

2012 ◽

Vol 20 (2) ◽

pp. 246-252 ◽

Cited By ~ 5

Author(s):

Andreia Assis Carvalho ◽

Francine do Couto Lima Moreira ◽

Rodrigo Borges Fonseca ◽

Carlos José Soares ◽

Eduardo Batista Franco ◽

...

Keyword(s):

Flexural Strength ◽

Composite Resin ◽

Light Sources ◽

Biaxial Flexural Strength ◽

Effect Of Light

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Effect of Low Shrinkage Monomers on Physicochemical Properties of Dental Resin Composites

Brazilian Dental Journal ◽

10.1590/0103-6440201300401 ◽

2015 ◽

Vol 26 (3) ◽

pp. 272-276 ◽

Cited By ~ 5

Author(s):

Dayane Carvalho Ramos Salles de Oliveira ◽

Karla Rovaris ◽

Viviane Hass ◽

Eduardo José Souza-Júnior ◽

Francisco Haiter-Neto ◽

...

Keyword(s):

Flexural Strength ◽

Physicochemical Properties ◽

Statistical Difference ◽

Resin Composite ◽

Multiple Comparisons ◽

Resin Composites ◽

Dental Resin ◽

Tukey Test ◽

Dental Resin Composites ◽

One Way Anova

The aim of this study was to evaluate the effect of low shrinkage monomers on physicochemical properties of dental resin composites. Two low shrinkage resin composites: one with a crosslink branching monomer (Kalore, GC Corp) and a novel monomer (Venus Diamond, Heraeus Kulzer) were compared to a conventional resin composite formulation (Filtek Z250, 3M/ESPE). The volumetric shrinkage was evaluated by µCT analysis (n=5) and the physicochemical properties by degree of C=C conversion (DC), flexural strength (FS) and Young's modulus (YM) (n=10). All samples were light cured by a LED device (Radii, SDI) with 16 J/cm2. The results were analysed by one-way ANOVA and Tukey test for multiple comparisons (α=0.05). No statistical difference was found between µCT shrinkage values to Kalore (1.8%) and Venus Diamond (1.7%) (p≥0.05); Z250 presented statistical highest shrinkage value (2.0%). Kalore presented higher statistical DC (60.8%) than Venus Diamond (49.5%) and Z250 (49.6%). No statistical difference was found between FS or YM properties to Venus Diamond and Z250; Kalore presented statistical lowest FS and YM properties (p≥0.05). Conclusion: Using novel monomers seem to reduce polymerization shrinkage without affecting the physicochemical properties evaluated of resin composites rather than using crosslink branching monomers.

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Durability of silorane repair with silorane and methacrylate resin.

Brazilian Dental Science ◽

10.14295/bds.2014.v17i2.971 ◽

2014 ◽

Vol 17 (2) ◽

pp. 27

Author(s):

Thays Regina Costa ◽

Lucielle Cristina Cecchin ◽

Alessandro Dourado Loguercio ◽

Alessandra Reis

Keyword(s):

Phosphoric Acid ◽

Aluminum Oxide ◽

Repeated Measures ◽

Composite Resin ◽

Nitrate Solution ◽

Water Storage ◽

Silver Nitrate Solution ◽

Composite Resins ◽

Repeated Measures Anova ◽

Bonded Interface

Objective: The durability of bonded interface between silorane (SIL) and methacrylate-based (MET) composite resins wasn’t investigated yet. The purpose was to evaluate the repair strength (RS) and nanoleakage of the SIL repair using silorane- or methacrylate-based materials immediately [IM] or after 6 months of water storage [6M]. Materials and Methods: fifteen resin blocks (Filtek P90, 3MESPE) were polished, sandblasted with 50-µm aluminum oxide sandblasting and cleaned with 37% phosphoric acid. Then the specimens were divided into three groups: SIL-SIL (adhesive and composite resin); SIL-MET (silorane adhesive and methacrylate based composite) and MET-MET (methacrylate-based adhesive and composite resin) were used for the repair. Composite-composite bonded sticks (0.9 mm2) were sectioned and divided to be tested in tension (1.0 mm/min) IM or 6M. Two sticks from each tooth, at each time, were immersed in a 50% silver nitrate solution and evaluated by SEM. Data were analyzed by two-way repeated measures ANOVA and Tukey´s tests. Results: The RS of the SIL was not dependent upon the adhesive and composite used for the repair. A significant reduction of the RS was observed for all groups after 6M. Conclusions: Both materials can be used for the repair of the silorane composite, despite degradation occur after 6M.

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Effect of Preheating and Fatiguing on Mechanical Properties of Bulk-fill and Conventional Composite Resin

Operative Dentistry ◽

10.2341/19-092-l ◽

2019 ◽

Vol 45 (4) ◽

pp. 387-395

Author(s):

AA Abdulmajeed ◽

TE Donovan ◽

R Cook ◽

TA Sulaiman

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Tensile Strength ◽

Elastic Modulus ◽

Flexural Strength ◽

Composite Resin ◽

Statistical Significance ◽

Composite Resins ◽

Significant Difference ◽

Diametral Tensile Strength

Clinical Relevance Bulk-fill composite resins may have comparable mechanical properties to conventional composite resin. Preheating does not reduce the mechanical properties of composite resins. SUMMARY Statement of Problem: Bulk-fill composite resins are increasingly used for direct restorations. Preheating high-viscosity versions of these composites has been advocated to increase flowability and adaptability. It is not known what changes preheating may cause on the mechanical properties of these composite resins. Moreover, the mechanical properties of these composites after mastication simulation is lacking. Purpose: The purpose of this study was to evaluate the effect of fatiguing and preheating on the mechanical properties of bulk-fill composite resin in comparison to its conventional counterpart. Methods and Materials: One hundred eighty specimens of Filtek One Bulk Fill Restorative (FOBR; Bulk-Fill, 3M ESPE) and Filtek Supreme Ultra (FSU; Conventional, 3M ESPE) were prepared for each of the following tests: fracture toughness (International Organization for Standardization, ISO 6872), diametral tensile strength (No. 27 of ANSI/ADA), flexural strength, and elastic modulus (ISO Standard 4049). Specimens in the preheated group were heated to 68°C for 10 minutes and in the fatiguing group were cyclically loaded and thermocycled for 600,000 cycles and then tested. Two-/one-way analysis of variance followed by Tukey Honest Significant Difference (HSD) post hoc test was used to analyze data for statistical significance (α=0.05). Results: Preheating and fatiguing had a significant effect on the properties of both FSU and FOBR. Fracture toughness increased for FOBR specimens when preheated and decreased when fatigued (p=0.016). FOBR had higher fracture toughness value than FSU. Diametral tensile strength decreased significantly after fatiguing for FSU (p=0.0001). FOBR had a lower diametral tensile strength baseline value compared with FSU (p=0.004). Fatiguing significantly reduced the flexural strength of both FSU and FOBR (p=0.011). Preheating had no effect on the flexural strength of either FSU or FOBR. Preheating and fatiguing significantly decreased the elastic modulus of both composite resins equally (p>0.05). Conclusions: Preheating and fatiguing influenced the mechanical properties of composite resins. Both composites displayed similar mechanical properties. Preheating did not yield a major negative effect on their mechanical properties; the clinical implications are yet to be determined.

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Flexural Strength of an Indirect Composite Modified with Single-Wall Carbon Nanotubes

European Journal of Dentistry ◽

10.1055/s-0040-1721315 ◽

2021 ◽

Author(s):

Pedro Rogério Camargos Pennisi ◽

Pedro Urquiza Jayme Silva ◽

Fábio Scorsolini Valverde ◽

Ticiane Campos Clemente ◽

Vitória Cerri ◽

...

Keyword(s):

Carbon Nanotubes ◽

Flexural Strength ◽

Composite Resin ◽

Composite Resins ◽

Single Wall Carbon Nanotubes ◽

Single Wall Carbon ◽

Dental Restorations ◽

Transmission Electron ◽

Indirect Composite ◽

Flexural Resistance

Abstract Objectives The low resistance to fracture has limited the use of indirect composite resins for dental restorations, particularly in regions that are exposed to strong occlusal forces. To overcome this issue, different types of reinforcement for composites have been proposed, one of which is carbon nanotubes (CNTs). The aim of this study was to evaluate the flexural resistance of one commercial indirect composite resin (Sinfony, 3M/ESPE) after incorporation of single-wall carbon nanotubes (SWCNTs; Sigma–Aldrich, Inc., St. Louis, Missouri, United States) with or without the silanization form. Materials and Methods Specimens of composite resin were fabricated in a Teflon mold. The composite resin was prepared according to the manufacturer’s instructions (n = 10 for each group), with SWCNTs in three concentrations. Statistical Analysis The SWCNTs and SWCNT/SiO2-ATES specimens were evaluated by transmission electron microscopy, and a flexural test was conducted according to the ISO 4049/2009. Flexural strength data in MPa were submitted to one-way ANOVA following Tukey (p < 0.05). Results The SWCNTs did not improve the flexural strength of indirect composite resin when compared with the control, independent of the concentration added (p > 0.05). However, when SWCNTs and SWCNTs/SiO2-ATES were compared, the SWCNTs/SiO2-ATES showed higher values than the three concentrations of SWCNTs (p < 0.05). Conclusion The silanization process improves the SWCNTs strength proprieties, but the modification of chemical bonding between SWCNT and SWCNT/SiO2-ATES modified resins, in different concentrations, did not improve the composite resin flexural strength.

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Effect of Light Curing Modes and Light Curing Time on the Microhardness of a Hybrid Composite Resin

The Journal of Contemporary Dental Practice ◽

10.5005/jcdp-8-6-1 ◽

2007 ◽

Vol 8 (6) ◽

pp. 1-8 ◽

Cited By ~ 17

Author(s):

José Roberto Lovadino ◽

Gláucia Maria Bovi Ambrosano ◽

Flávio Henrique Baggio Aguiar ◽

Aline Braceiro ◽

Débora Alves Nunes Leite Lima

Keyword(s):

Hybrid Composite ◽

High Intensity ◽

Composite Resin ◽

Resin Composite ◽

Composite Resins ◽

Bottom Surface ◽

Curing Time ◽

Experimental Conditions ◽

Light Curing ◽

Effect Of Light

Abstract Aims The aim of this in vitro study was to evaluate the influence of light curing modes and curing time on the microhardness of a hybrid composite resin. Methods and Materials Forty-five Z250 composite resin specimens (3M-ESPE Dental Products, St. Paul, MN, USA) were randomly divided into nine groups (n=5): three polymerization modes (conventional - 550 mW/ cm2; light-emitting diodes (LED) - 360mW/cm2, and high intensity - 1160 mW/cm2) and three light curing times (once, twice, and three times the manufacturer's recommendations). All samples were polymerized with the light tip 8 mm from the specimen. Knoop microhardness measurements were obtained on the top and bottom surfaces of the sample. Results Conventional and LED polymerization modes resulted in higher hardness means and were statistically different from the high intensity mode in almost all experimental conditions. Tripling manufacturers’ recommended light curing times resulted in higher hardness means; this was statistically different from the other times for all polymerization modes in the bottom surface of specimens. This was also true of the top surface of specimens cured using the high intensity mode but not of conventional and LED modes using any of the chosen curing times. Top surfaces showed higher hardness than bottom surfaces. Conclusions It is important to increase the light curing time and use appropriate light curing devices to polymerize resin composite in deep cavities to maximize the hardness of hybrid composite resins. Citation Aguiar FHB, Braceiro A, Lima DANL, Ambrosano GMB, Lovadino JR. Effect of Light Curing Modes and Light Curing Time on the Microhardness of a Hybrid Composite Resin. J Contemp Dent Pract 2007 September; (8)6:001-008.

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Mechanical Degradation of Different Classes of Composite Resins Aged in Water, Air, and Oil

BioMed Research International ◽

10.1155/2019/7410759 ◽

2019 ◽

Vol 2019 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

Weber Adad Ricci ◽

Priscila Alfano ◽

Saulo Pamato ◽

Carlos Alberto dos Santos Cruz ◽

Jefferson Ricardo Pereira

Keyword(s):

Flexural Strength ◽

Storage Time ◽

Composite Resin ◽

Composite Resins ◽

Mechanical Degradation ◽

Hardness Testing ◽

Significant Deterioration ◽

Strength Tests ◽

Group A ◽

And Storage

A significant deterioration of the properties can drastically compromise the survival rate of restorative materials. The aim of this study was to assess flexural strength and hardness of three composite classes: hybrid composite resin (HCR), nanoparticulate composite resin (NCR), and silorane-based composite resin (SBCR). One hundred specimens were prepared for hardness testing by using a split metallic mold measuring 10 mm in diameter and 2 mm deep. Twenty specimens were prepared for each restorative material, randomly assigned for storage in air, distilled water, or mineral oil. After intervals of 24 hours, 30, 60, 90, and 120 days, hardness and flexural strength tests were initially compared in two levels: “storage medium” and “time” within each material group. A two-way analysis of variance was performed (p<0.05) on the variables “material” and “storage time” (p<0.05). The HCR showed to be stable with regard to the evaluation of flexural strength and hardness (p<0.05). A significant reduction occurs for the NCR in comparison to the other groups (p<0.05). The NCR presented the lowest values of hardness and flexural strength kept on water over time. The characteristics of material showed a strong influence on the decrease of the mechanical properties analyzed.

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Influence of light curing source on microhardness of composite resins of different shades

Journal of Applied Oral Science ◽

10.1590/s1678-77572006000100003 ◽

2006 ◽

Vol 14 (1) ◽

pp. 10-15 ◽

Cited By ~ 8

Author(s):

André Luiz Fraga Briso ◽

Tânia Maria Fedel ◽

Sibéria de Morais Pereira ◽

Sílvio José Mauro ◽

Renato Herman Sundfeld ◽

...

Keyword(s):

Light Intensity ◽

Confidence Level ◽

Composite Resin ◽

Composite Resins ◽

The Other ◽

Light Sources ◽

Low Light ◽

Tukey Test ◽

Light Curing ◽

Hardness Values

INTRODUCTION: The evolution of light curing units can be noticed by the different systems recently introduced. The technology of LED units promises longer lifetime, without heating and with production of specific light for activation of camphorquinone. However, further studies are still required to check the real curing effectiveness of these units. PURPOSE: This study evaluated the microhardness of 4 shades (B-0.5, B-1, B-2 and B-3) of composite resin Filtek Z-250 (3M ESPE) after light curing with 4 light sources, being one halogen (Ultralux - Dabi Atlante) and three LED (Ultraled - Dabi Atlante, Ultrablue - DMC and Elipar Freelight - 3M ESPE). METHODS: 192 specimens were distributed into 16 groups, and materials were inserted in a single increment in cylindrical templates measuring 4mm x 4mm and light cured as recommended by the manufacturer. Then, they were submitted to microhardness test on the top and bottom aspects of the cylinders. RESULTS: The hardness values achieved were submitted to analysis of variance and to Tukey test at 5% confidence level. It was observed that microhardness of specimens varied according to the shade of the material and light sources employed. The LED appliance emitting greater light intensity provided the highest hardness values with shade B-0.5, allowing the best curing. On the other hand, appliances with low light intensity were the least effective. It was also observed that the bottom of specimens was more sensitive to changes in shade. CONCLUSION: Light intensity of LED light curing units is fundamental for their good functioning, especially when applied in resins with darker shades.

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Comparison of time-dependent changes in the surface hardness of different composite resins

European Journal of Dentistry ◽

10.4103/1305-7456.119059 ◽

2013 ◽

Vol 07 (S 01) ◽

pp. S020-S025 ◽

Cited By ~ 1

Author(s):

Suat Ozcan ◽

Ihsan Yikilgan ◽

Mine Betul Uctasli ◽

Oya Bala ◽

Zeliha Gonca Bek Kurklu

Keyword(s):

Composite Resin ◽

Surface Hardness ◽

Multiple Comparisons ◽

Composite Resins ◽

Time Dependent ◽

Bottom Surface ◽

Significance Level ◽

Hardness Tester ◽

Significant Difference ◽

Hardness Values

ABSTRACT Objective: The aim of this study was to evaluate the change in surface hardness of silorane-based composite resin (Filtek Silorane) in time and compare the results with the surface hardness of two methacrylate-based resins (Filtek Supreme and Majesty Posterior). Materials and Methods: From each composite material, 18 wheel-shaped samples (5-mm diameter and 2-mm depth) were prepared. Top and bottom surface hardness of these samples was measured using a Vicker′s hardness tester. The samples were then stored at 37°C and 100% humidity. After 24 h and 7, 30 and 90 days, the top and bottom surface hardness of the samples was measured. In each measurement, the rate between the hardness of the top and bottom surfaces were recorded as the hardness rate. Statistical analysis was performed by one-way analysis of variance, multiple comparisons by Tukey′s test and binary comparisons by t-test with a significance level of P = 0.05. Results: The highest hardness values were obtained from each two surfaces of Majesty Posterior and the lowest from Filtek Silorane. Both the top and bottom surface hardness of the methacrylate based composite resins was high and there was a statistically significant difference between the top and bottom hardness values of only the silorane-based composite, Filtek Silorane (p < 0.05). The lowest was obtained with Filtek Silorane. The hardness values of all test groups increased after 24 h (p < 0.05). Conclusions: Although silorane-based composite resin Filtek Silorane showed adequate hardness ratio, the use of incremental technic during application is more important than methacrylate based composites.

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