scholarly journals The Influence of Various Photoinitiators on the Properties of Commercial Dental Composites

Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3972
Author(s):  
Andrea Kowalska ◽  
Jerzy Sokolowski ◽  
Tomasz Gozdek ◽  
Michał Krasowski ◽  
Karolina Kopacz ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Flexural Strength ◽  
Biomechanical Properties ◽  
Dental Composites ◽  
Polymerization Shrinkage ◽  
Contraction Stress ◽  
Photoelastic Analysis ◽  
Diametral Tensile Strength

The aim of this article was to compare the biomechanical properties of commercial composites containing different photoinitiators: Filtek Ultimate (3M ESPE) containing camphorquinone (CQ); Estelite Σ Quick (Tokuyama Dental) with CQ in RAP Technology®; Tetric EvoCeram Bleach BLXL (Ivoclar Vivadent AG) with CQ and Lucirin TPO; and Tetric Evoceram Powerfill IVB (Ivoclar Vivadent AG) with CQ and Ivocerin TPO. All samples were cured with a polywave Valo Lamp (Ultradent Products Inc.) with 1450 mW/cm2. The microhardness, hardness by Vicker’s method, diametral tensile strength, flexural strength and contraction stress with photoelastic analysis were tested. The highest hardness and microhardness were observed for Filtek Ultimate (93.82 ± 17.44 HV), but other composites also displayed sufficient values (from 52 ± 3.92 to 58,82 ± 7.33 HV). Filtek Ultimate not only demonstrated the highest DTS (48.03 ± 5.97 MPa) and FS (87.32 ± 19.03 MPa) but also the highest contraction stress (13.7 ± 0.4 MPa) during polymerization. The TetricEvoCeram Powerfill has optimal microhardness (54.27 ± 4.1 HV), DTS (32.5 ± 5.29 MPa) and FS (79.3 ± 14.37 MPa) and the lowest contraction stress (7.4 ± 1 MPa) during photopolymerization. To summarize, Filtek Ultimate demonstrated the highest microhardness, FS and DTS values; however, composites with additional photoinitiators such as Lucirin TPO and Ivocerin have the lowest polymerization shrinkage. These composites also have higher FS and DTS and microhardness than material containing CQ in Rap Technology.

scholarly journals The influence of filler amount on selected properties of new experimental resin dental composite

2018 ◽  
Vol 16 (1) ◽  
pp. 905-911 ◽  
Author(s):  
Kinga Bociong ◽  
Agata Szczesio ◽  
Michal Krasowski ◽  
Jerzy Sokolowski
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Flexural Strength ◽  
Dental Composite ◽  
Neat Resin ◽  
Light Curing ◽  
Contraction Stress ◽  
Silanized Silica ◽  
Composite Hardness ◽  
Diametral Tensile Strength

AbstractAim of the study was to evaluate the influence of filler amounts on mechanical properties and contraction stress of light-curing experimental composite. Hardness, flexural strength, diametral tensile strength of material filled with 40, 50 or 60 wt. % of silanized silica were tested. The contraction stress was measured after 24 h by means of photoelastic study. The addition of 40-60 wt. % filler to composite caused significant increase in hardness, Young’s modulus and flexural strength. The DTS, after incorporating filler into polymer matrix, was valued at ~26 MPa. The composite containing 40 wt. % of filler demonstrated significantly lower contraction stress in comparison to neat resin and filled > 50 wt. % of silica.

Diametral tensile strength and dental composites

1987 ◽  
Vol 3 (1) ◽  
pp. 46-48 ◽  
Author(s):  
R.W. Penn ◽  
R.G. Craig ◽  
J.A. Tesk
Keyword(s):  
Tensile Strength ◽  
Dental Composites ◽  
Diametral Tensile Strength

scholarly journals The Biomechanical Properties of Rattan Cane in the Design and Fabrication of Prosthetic Foot

2020 ◽  
Vol 8 (6) ◽  
Author(s):  
Kelechi D. Kelechi ◽  
Gideon I. N. Ndubuka ◽  
Kingsley C. Onwukamuche ◽  
Micheal C. Ofoegbu ◽  
Ugochi C. Elueke ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Ultimate Tensile Strength ◽  
Flexural Strength ◽  
Load Resistance ◽  
Biomechanical Properties ◽  
Biomechanical Analysis ◽  
Heel Strike ◽  
Prosthetic Foot ◽  
Rattan Cane

In designing prosthetics for amputees, quality and quantity of materials determine device tensile, flexural, extension and compression strength as well as energy distribution when load is applied. Biomechanical properties contribute in combination to any device longevity and resolution force effect to gait expression. Four different dry rattan canes were sampled and subjected to biomechanical analysis, and sample 3 had highest tensile strength with ultimate tensile strength of 11.5N/mm2 revealed when load at break of 668.18N applied, and modulus 1033.90MPa with ductility of 7.33mm were resultant. While average ultimate tensile strength of 8.68N/mm2 was sustained by load at break of 396.66N, modulus of 1119MPa and ductility of 9.5mm was confirmed of rattan cane. Highest flexural strength of 34.43N/mm2 resulted from load at break of 32.82N, modulus 255.65MPa and elongation of 66.81mm was dictated of sample 3, and an average Flexural strength of 26.4 N/mm2 occurred when load at break of 16.04N, modulus 229.16MPa produced elongation (ductility) of 55.1mm on rattan cane. The highest load resistance was shown by sample 3 at compressive strength of 8.79MPa when on load at break of 330N, modulus 622.53MPa resulted. While sample 4 had the highest compressive strength of 9.94MPa when load break at 309N exerted modulus 283.14MPa. Gait analysis revealed terminal swing and heel strike of chosen height 8cm and deformity 0cm while early and mid stance of 0.3cm and 7.7cm were respectively for deformity and height.

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

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.

Influence of Ketones on Selected Mechanical Properties of Resin Composites

1992 ◽  
Vol 71 (11) ◽  
pp. 1847-1850 ◽  
Author(s):  
A. Peutzfeldt ◽  
E. Asmussen
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Flexural Strength ◽  
Modulus Of Elasticity ◽  
Cross Linking ◽  
Resin Composites ◽  
Light Curing ◽  
Resistance To Wear ◽  
Modulus Of Resilience ◽  
Diametral Tensile Strength

The present study investigated a concept for additional crosslinking of dental polymers, by which resistance to wear of resin composites might be increased. Bifunctional ketones were added to monomer mixtures, which were then made light-curing and loaded with filler. The monomer mixtures were varied with respect to type and ratio of monomer and ketone. For measurement of possible effects of the cross-linking agents added, four mechanical properties of the experimental resin composites were determined. Addition of the bifunctional ketone diacetyl resulted in the following increases in mechanical properties: diametral tensile strength, 11%; flexural strength, 29%; modulus of elasticity, 19%; and modulus of resilience, 50%.

scholarly journals A Comparative Study of the Mechanical Properties of Selected Dental Composites with a Dual-Curing System with Light-Curing Composites

Coatings ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1255
Author(s):  
Monika Domarecka ◽  
Agata Szczesio-Wlodarczyk ◽  
Michał Krasowski ◽  
Magdalena Fronczek ◽  
Tomasz Gozdek ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Flexural Strength ◽  
Comparative Study ◽  
Wide Spectrum ◽  
Shrinkage Stress ◽  
Three Point Bending ◽  
Light Curing ◽  
Dual Curing ◽  
Diametral Tensile Strength

Dual-curing composites have a wide spectrum of use in practice (rebuilding, reconstruction, and luting). The characterization of this type of material and comparative study of selected mechanical properties with light-cured materials were carried out for this paper. In this study, we used six materials with a dual-cure system—Bulk EZ, Fill-Up!, StarFill 2B, Rebilda DC, MultiCore Flow, Activa Bioactive-Restorative—and three light-cured materials—Filtek Bulk Fill Posterior, Charisma Classic, and G-aenial Universal Flo. The materials were conditioned for 24 h in water at 37 °C before testing. Selected material properties were determined: three-point bending flexural strength, diametral tensile strength, hardness, microhardness, and shrinkage stress. The highest three-point bending flexural strength (TPB) was 137.0 MPa (G-aenial Universal Flo), while the lowest amounted to 86.5 MPa (Activa Bioactive). The diametral tensile strength (DTS) values were in a range from 39.2 MPa (Rebilda DC) to 54.1 MPa (Charisma Classic). The lowest hardness (HV) value of 26 was obtained by the Activa Bioactive material, while the highest values were recorded for Filtek Bulk Fill Posterior and Charisma Classic-53. The shrinkage stress of the tested materials ranged from 6.3 MPa (Charisma Classic) to 13.2 MPa (G-aenial Universal Flo). Dual-curing composites were found to have similar properties to light-cured composites.

scholarly journals An in vitro Evaluation of Diametral Tensile Strength and Flexural Strength of Nanocomposite vs Hybrid and Minifill Composites cured with Different Light Sources (QTH vs LED)

2013 ◽  
Vol 14 (1) ◽  
pp. 84-89
Author(s):  
K Venkata Srikanth ◽  
Surendra Nath Garapati ◽  
Priyadarshini LNU ◽  
Piyush Raturi ◽  
Dinesh Shetty
Keyword(s):  
Tensile Strength ◽  
Flexural Strength ◽  
New Technology ◽  
Testing Machine ◽  
Light Sources ◽  
Soft Start ◽  
Two Samples ◽  
Nanocomposite System ◽  
Diametral Tensile Strength

ABSTRACT Background Composites always remained the target of discussion due to lot of controversies around it. Mechanical properties are one of them. With the introduction of new technology and emergence of various composites which combine superior strength and polish retention, nanocomposites have led to a new spark in the dentistry. A recent curing unit LED with various curing modes claims to produce higher degree of conversion. The aim of this study was to evaluate the diametral tensile strength and flexural strength of nanocomposite, hybrid and minifill composites cured with different light sources (QTH vs LED). Materials and methods Seventy-two samples were prepared using different specially fabricated teflon molds, 24 samples of each composite were prepared for the diametral tensile strength (ADA specification no. 27) and the flexural strength (ISO 4049) of the 12 samples, six were cured with LED (Soft Start curing profile) and other six with QTH curing light and tested on a universal testing machine. Results The nanocomposite had highest diametral tensile strength and flexural strength which were equivalent to the hybrid composite and superior than the minifill composite. Conclusion With the combination of superior esthetics and other optimized physical properties, this novel nanocomposite system would be useful for all posterior and anterior applications. How to cite this article Garapati SN, Priyadarshini, Raturi P, Shetty D, Srikanth KV. An in vitro Evaluation of Diametral Tensile Strength and Flexural Strength of Nanocomposite vs Hybrid and Minifill Composites cured with Different Light Sources (QTH vs LED). J Contemp Dent Pract 2013;14(1):84-89.

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