Influence of resin matrix on the rheology, translucency, and curing potential of experimental flowable composites for bulk-fill applications

Author(s):  
Leonardo Duarte Eiras Pereira ◽  
Mário Pereira Couto Neto ◽  
Roberto Guimarães Pereira ◽  
Luis Felipe J. Schneider
2014 ◽  
Vol 631 ◽  
pp. 143-150 ◽  
Author(s):  
María Arregui ◽  
Luís Giner ◽  
Marco Ferrari ◽  
Montserrat Mercadé

Objectives:The aim of this study was to compare colour stability of two self-adhesive flowable composites with four methacrylate-based composites (three flowable composites and one universal resin-based composite) after immersion in water at 60°C for 30 days.Methods:The study was conducted using the following five shade A2 flowable composites (n=30): one microhybrid (G-aenial Universal Flo), one universal (X-Flow), one nanohybrid (Premise flowable) and two self-adhesive (Vertise Flow and experimental GF-10) and one microhybrid universal resin-based composite (G-aenial Posterior). A spectrophotometer (CIEL*a*b* system) was used to measure colour stability before and after immersion. Statistical analysis was performed with one-way ANOVA and Fisher test.Results:Samples immersed in water at 60°C for one month showed a significant colour change in all groups (p<.001) that was visually perceptible (∆E>3.3). Experimental self-adhesive flowable (12.25±0.84) and X-Flow (11.56±3.26) composites showed higher levels of ∆E, while Premise flowable showed a lower level of colour change (3.47±1.26). These results approximated clinically acceptable colour change values (∆E≤3.3). Water ageing at 60°C produced a significant change in colour in all the composites. The high temperature may explain the degradation of the resin matrix.


2021 ◽  
Vol 41 (3) ◽  
pp. 1810-1816
Author(s):  
Zhenyue Zou ◽  
Yan Qin ◽  
Huadong Fu ◽  
Di Zhu ◽  
Zhuangzhuang Li ◽  
...  

2021 ◽  
pp. 51305
Author(s):  
Nora Abigail Wilson García ◽  
Jorge Luis Almaral Sánchez ◽  
Ramón Álvaro Vargas Ortiz ◽  
Abel Hurtado Macías ◽  
Nelly Flores Ramírez ◽  
...  

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 338
Author(s):  
Ali Alrahlah ◽  
Abdel-Basit Al-Odayni ◽  
Haifa Fahad Al-Mutairi ◽  
Bashaer Mousa Almousa ◽  
Faisal S. Alsubaie ◽  
...  

This study aimed to synthesize new bisphenol A-glycidyl methacrylate (BisGMA) derivatives, targeting a reduction in its viscosity by substituting one of its OH groups, the leading cause of its high viscosity, with a chlorine atom. Hence, this monochloro-BisGMA (mCl-BisGMA) monomer was synthesized by Appel reaction procedure, and its structure was confirmed using Fourier transform infrared spectroscopy, 1H and 13C-nuclear magnetic resonance spectroscopy, and mass spectroscopy. The viscosity of mCl-BisGMA (8.3 Pa·s) was measured under rheometry conditions, and it was found to be more than 65-fold lower than that of BisGMA (566.1 Pa·s) at 25 °C. For the assessment of the viscosity changes of model resins in the presence of mCl-BisGMA, a series of resin matrices, in which, besides BisGMA, 50 wt % was triethylene glycol dimethacrylate, were prepared and evaluated at 20, 25, and 35 °C. Thus, BisGMA was incrementally replaced by 25% mCl-BisGMA to obtain TBC0, TBC25, TBC50, TBC75, and TBC100 blends. The viscosity decreased with temperature, and the mCl-BisGMA content in the resin mixture increased. The substantial reduction in the viscosity value of mCl-BisGMA compared with that of BisGMA may imply its potential use as a dental resin matrix, either alone or in combination with traditional monomers. However, the various properties of mCl-BisGMA-containing matrices should be evaluated.


2019 ◽  
Vol 138 ◽  
pp. 681-692 ◽  
Author(s):  
Marina G. Holyavka ◽  
Maxim S. Kondratyev ◽  
Anatoly N. Lukin ◽  
Boris L. Agapov ◽  
Valery G. Artyukhov

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2127
Author(s):  
Richard Fürst ◽  
Eliška Fürst ◽  
Tomáš Vlach ◽  
Jakub Řepka ◽  
Marek Pokorný ◽  
...  

Textile-reinforced concrete (TRC) is a material consisting of high-performance concrete (HPC) and tensile reinforcement comprised of carbon roving with epoxy resin matrix. However, the problem of low epoxy resin resistance at higher temperatures persists. In this work, an alternative to the epoxy resin matrix, a non-combustible cement suspension (cement milk) which has proven stability at elevated temperatures, was evaluated. In the first part of the work, microscopic research was carried out to determine the distribution of particle sizes in the cement suspension. Subsequently, five series of plate samples differing in the type of cement and the method of textile reinforcement saturation were designed and prepared. Mechanical experiments (four-point bending tests) were carried out to verify the properties of each sample type. It was found that the highest efficiency of carbon roving saturation was achieved by using finer ground cement (CEM 52.5) and the pressure saturation method. Moreover, this solution also exhibited the best results in the four-point bending test. Finally, the use of CEM 52.5 in the cement matrix appears to be a feasible variant for TRC constructions that could overcome problems with its low temperature resistance.


Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1112
Author(s):  
Raghvendra Singh Yadav ◽  
Anju ◽  
Thaiskang Jamatia ◽  
Ivo Kuřitka ◽  
Jarmila Vilčáková ◽  
...  

Superparamagnetic ZnFe2O4 spinel ferrite nanoparticles were prepared by the sonochemical synthesis method at different ultra-sonication times of 25 min (ZS25), 50 min (ZS50), and 100 min (ZS100). The structural properties of ZnFe2O4 spinel ferrite nanoparticles were controlled via sonochemical synthesis time. The average crystallite size increases from 3.0 nm to 4.0 nm with a rise of sonication time from 25 min to 100 min. The change of physical properties of ZnFe2O4 nanoparticles with the increase of sonication time was observed. The prepared ZnFe2O4 nanoparticles show superparamagnetic behavior. The prepared ZnFe2O4 nanoparticles (ZS25, ZS50, and ZS100) and reduced graphene oxide (RGO) were embedded in a polyurethane resin (PUR) matrix as a shield against electromagnetic pollution. The ultra-sonication method has been used for the preparation of nanocomposites. The total shielding effectiveness (SET) value for the prepared nanocomposites was studied at a thickness of 1 mm in the range of 8.2–12.4 GHz. The high attenuation constant (α) value of the prepared ZS100-RGO-PUR nanocomposite as compared with other samples recommended high absorption of electromagnetic waves. The existence of electric-magnetic nanofillers in the resin matrix delivered the inclusive acts of magnetic loss, dielectric loss, appropriate attenuation constant, and effective impedance matching. The synergistic effect of ZnFe2O4 and RGO in the PUR matrix led to high interfacial polarization and, consequently, significant absorption of the electromagnetic waves. The outcomes and methods also assure an inventive and competent approach to develop lightweight and flexible polyurethane resin matrix-based nanocomposites, consisting of superparamagnetic zinc ferrite nanoparticles and reduced graphene oxide as a shield against electromagnetic pollution.


Sign in / Sign up

Export Citation Format

Share Document