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CLSM images of biofilm formed by S. sanguinis, S. mutans, and mixed species: S. sanguinis and S. mutans on B, BM, F, FM composite materials in BHI medium (a) and in BHI + 0.25% sucrose medium (b). Magn. 400×, scale bar = 70 μm (green fluorescence-viable cells, yellow and red fluorescence-dead cells).
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The aim of this study was to evaluate the effect of modification with liquid rubber on the adhesion to tooth tissues (enamel, dentin), wettability and ability to inhibit bacterial biofilm formation of resin-based dental composites. Two commercial composites (Flow-Art–flow type with 60% ceramic filler and Boston–packable type with 78% ceramic filler...
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... obtained with the quantitative assay were next confirmed by biofilm determination with the use of CLSM. The CLSM images presented in Figure 4a,b show S. mutans and S. sanguinis mono- and mixed-species biofilm on the materials surface with viable (stained green) and dead colonies (stained yellow-red). Surface of the disc without biofilm is visible as a non-stained area (no fluorescent signal-black color). ...
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... dead bacteria (red colonies) and some small green colonies (formed by viable bacteria) were observed on the tested composite discs. The images clearly demonstrate weaker adhesion of the bacteria to the modified FM, BM samples as well as to the unmodified F and B discs in comparison to the control (Figure 4a,b). However, the weakest bacteria adhesion was observed on the FM composite that contained liquid rubber and lower content of ceramics compared to packable type composites. ...
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... obtained with the quantitative assay were next confirmed by biofilm determination with the use of CLSM. The CLSM images presented in Figure 4a,b show S. mutans and S. sanguinis mono- and mixed-species biofilm on the materials surface with viable (stained green) and dead colonies (stained yellow-red). Surface of the disc without biofilm is visible as a non-stained area (no fluorescent signal-black color). ...
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... dead bacteria (red colonies) and some small green colonies (formed by viable bacteria) were observed on the tested composite discs. The images clearly demonstrate weaker adhesion of the bacteria to the modified FM, BM samples as well as to the unmodified F and B discs in comparison to the control (Figure 4a,b). However, the weakest bacteria adhesion was observed on the FM composite that contained liquid rubber and lower content of ceramics compared to packable type composites. ...
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Biofilm development on surfaces leads to biofouling, which is an undesirable phenomenon in the marine industry. Marine fouling leads to an increase in fuel consumption and corrosion of propeller blades. Most of the antifouling technologies available today are chemical methods that have detrimental effects on the environment. The current work focuse...
Citations
... The time of irradiation, effective wavelength, and light intensity of the curing lamp, and its distance from the material's surface all influence the curing depth [22]. Due to incomplete conversion, as well as aging, mechanical weardown, hydrolysis, and enzymatic degradation over time, the elution of uncured, leachable monomers-as well as initiators and other additives-into the liquids of the oral cavity occurs [3,4,7,11,12,[24][25][26]. ...
... The time of irradiation, effective wavelength, and light intensity of the curing lamp, and its distance from the material's surface all influence the curing depth [22]. Due to incomplete conversion, as well as aging, mechanical weardown, hydrolysis, and enzymatic degradation over time, the elution of uncured, leachable monomers-as well as initiators and other additives-into the liquids of the oral cavity occurs [3,4,7,11,12,[24][25][26]. RBCs consist of an organic resin matrix (typically 15-50% of its weight), inorganic filler particles (reinforcing phase), a coupling agent, and a photo-initiator [5,8,19,22,27]. ...
The dental material industry is rapidly developing resin-based composites (RBCs), which find widespread use in a variety of clinical settings. As such, their biocompatibility has gained increasing interest. This literature review presents a summary of research into the cytotoxicity of methacrylate-based composites published from 2017 to 2023. Subject to analysis were 14 in vitro studies on human and murine cell lines. Cytotoxicity in the included studies was measured via MTT assay, LDH assay, and WST-1 assay. The QUIN Risk of Bias Tool was performed to validate the included studies. Included studies (based entirely on the results of in vitro studies) provide evidence of dose- and time-dependent cytotoxicity of dental resin-based composites. Oxidative stress and the depletion of cellular glutathione (GSH) were suggested as reasons for cytotoxicity. Induction of apoptosis by RBCs was indicated. While composites remain the golden standard of dental restorative materials, their potential cytotoxicity cannot be ignored due to direct long-term exposure. Further in vitro investigations and clinical trials are required to understand the molecular mechanism of cytotoxicity and produce novel materials with improved safety profiles.
... These materials are not attractive in terms of the considered solution, although they may be an interesting proposition in the case of applications requiring lower mechanical properties. Pałka et al. [8] investigated the influence of the addition of liquid rubber (methacrylate-terminated polybutadiene) on the properties of dental composites. The experimental materials presented enhanced shear bond strength values for enamel and dentine, reduced hydrophilicity, and reduced biofilm activity (Steptococcus mutans, Streptococcus sanguinis); however, they may show cytotoxicity for some formulations. ...
Billions of people suffer from dental problems and that number is constantly increasing [...]
... This phase is usually liquid rubber or rubber, and the strengthening mechanisms of resins using an elastic phase is called rubber toughening (RT) or rubber modification [2]. Modifying the matrix of dental composites can not only increase fracture toughness but also reduce polymerization shrinkage [5] while increasing the conversion [6] and adhesion to tooth tissues [7]. The problem of modifying the resins with liquid rubber has been broadly described for epoxy resin [2,8,9], while only a few studies focused on the modification of dimethacrylate resins [10]. ...
Fracture toughness is one of the main factors influencing the durability of light-cured composites used for dental restorations and fillings. One of the methods of increasing the fracture toughness is the modification of the matrix with liquid acrylonitrile-free liquid rubber. This study aimed to assess the miscibility of acrylonitrile-free liquid rubber with a blend of resins and their stability over time, and to determine the optimal amount of liquid rubber (LR) in the blend due to mechanical properties. Two blends of dimethacrylate resins were used: resin “F” composed of BisGMA (60 wt.%), TEGDMA (20 wt.%), BisEMA (10 wt.%) and UDMA (10 wt.%), and “C” resin containing BisGMA (40 wt.%), TEGDMA (40 wt.%), BisEMA (10 wt.%) and UDMA (10 wt.%). The modifier Hypro® 2000X168LC VTB liquid rubber was used in at 1%, 2%, 3%, 4%, 5%, 10%, 15% and 20% by weight in the resin blend. The miscibility was assessed by microscopy. The fracture toughness, flexural strength and Young’s modulus were determined in the bending test. The results showed that the solubility of the liquid rubber depends on the ratio of BisGMA/TEGDMA in the resins. In resins with 40 wt.% TEGDMA, the LR solubility was as high as 5%, while resins with 20 wt.% TEGDMA, the liquid rubber did not dissolve. The LR-resin mixtures showed good time stability, and no changes in the size or morphology of the rubber domains were found after 24 h of mixing. The maximum fracture toughness (2.46 MPa m1/2) was obtained for 5 wt.% LR in resin F and for 15 wt.% LR in resin C (2.53 MPa m1/2). The modification with liquid rubber resulted in an exponential reduction in both flexural strength and Young’s modulus. The analysis of the results of the mechanical tests allowed us to determine the optimal amount of LR for both resins. For resin F it was 5.4 wt.%, and for resin C it was 8.3 wt.%. It can be stated that the optimal amount of liquid rubber increases with its solubility in the resin.
... There are two -CNO groups in each tetramethyl-terephthalobisnitrile oxide (TTNO) molecule. Liquid polybutadiene (abbreviated as liquid PB), also known as the low-molecular-weight polybutadiene, is a low-molecular-weight polybutadiene and is a liquid rubber without functional groups (except double bond) [25,26]. It is often used as a toughener for epoxy resin adhesives. ...
As a significant component of composite solid propellants, the cross-link alkenyl polymers need to cure at high temperatures and the current isocyanate curing systems are highly humidity sensitive. This paper presented a low-temperature curing method for a cross-linked polymer (polybutadiene) with stable wettability by using cycloaddition of the nitrile oxide of tetramethyl-terephthalobisnitrile oxide (TTNO) and the C=C group of liquid polybutadiene (PB). The TTNO was synthesized in four steps from 1,2,4,5-tetramethylbenzene and evaluated as a low-temperature hardener for curing liquid PB. To characterize the reaction ability of TTNO at 25 °C, the cross-linked rubber materials of various contents (8%, 10%, 12%, 14%, 16%) of curing agent TTNO were prepared. The feasibility of the curing method can be proved by the disappearance of the absorption peak of the nitrile oxide group (2300 cm−1) by FT-IR analysis. Contact angle, TG-DTA and tensile-test experiments were conducted to characterize the wettability, thermo-stability and mechanical properties of the obtained cross-linked rubber materials, respectively. The results showed that the curing agent TTNO could cure PB at room temperature. With the growing content of the curing agent TTNO, the tensile strength of the obtained cross-linked rubber material increased by 260% and the contact angle increased from 75.29° to 89.44°. Moreover, the thermo-stability performances of the cross-linked rubber materials have proved to be very stable, even at a temperature of 300 °C, by TGA analysis.
