Amount Of Triethylene Glycol Dimethacrylate Research Articles

UV‐cured epoxy‐acrylate interpenetrating polymer networks with different contents of epoxidized soybean oil

AbstractThis work aims to study the effect of epoxidized soybean oil (ESO) concentration on the process of formation and characteristics of UV‐cured ternary epoxy‐acrylate interpenetrating polymer networks (IPNs). Whereas the amount of triethylene glycol dimethacrylate (TEGDMA) keeps constant, the one of ESO incorporated to substitute the respective quantity of diglycidyl ether of bisphenol A (DGEBA) is equal to 10, 20, and 30 parts by weight (pbw). A total of 30 pbw of ESO is found to be the most effective content for altering the conversion degree of epoxy groups and for enhancing the impact resistance of cured materials while providing their transparency. The addition of ESO induces the decrease in cross‐linking density and in the values of glass transition temperature. The samples exhibite good water and chemical resistance with some variations dependent on their composition. Thermooxidative stability of the specimens gradually reduces as the content of aromatic epoxy decreases. Overall, the introduction of ESO into epoxy‐acrylate IPNs not only lessens the fraction of synthetic epoxide but also facilitates the photopolymerization process of DGEBA and diminishes its brittleness. Considering fine atmospheric resistance testified by accelerated weathering test, given materials may be purposed as transparent films or protective coatings for both indoor and outdoor applications.

TEGDMA releasing in resin composites with different filler contents and its correlation with mitochondrial mediated cytotoxicity in human gingival fibroblasts.

Compositions of resin composite exhibit cytotoxicity, especially Triethylene-glycol-dimethacrylate (TEGDMA), yet the underlying mechanisms and its relationship with filler content are poorly understood. Here, specimens of five composites (VITA LC, VITA ZETA, Z350, Filtek P60, and AP-X), containing different filler size and weight, were immersed into culture medium for 72 h. After TEGDMA quantification, the resin composite eluates were used to incubate HGFs. Cellular viability was evaluated. Total reactive oxygen species (ROS) and mitochondrial ROS were detected to assess oxidative stress. Adenosine triphosphate and cytochrome c oxidase (CcO) activity, mitochondrial membrane potential and morphology, mitochondrial biogenesis regulators were analyzed to evaluate mitochondrial functions. Results showed that TEGDMA release negatively correlated to filler size and weight of tested composites. Although cell viability reduction was not significant, total and mitochondrial ROS production showed a positive relationship with the amount of TEGDMA in composite eluates. Furthermore, the expression of mitochondrial biogenesis markers and mitochondrial fusion protein, were markedly elevated in TEGDMA rich eluates, especially in VITA-LC group, shown as elongated mitochondrial morphology and aberrant mitochondrial functions. Overall, TEGDMA could elute easier from those resin composites with less filler content and cause oxidative stress in HGFs via mitochondria dysregulation. These data can be instructive to optimize the synthesis of resin composites from the perspective of biocompatibility. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1132-1142, 2019.

TEGDMA and UDMA monomers released from composite dental material polymerized with diode and halogen lamps.

More than 35 substances released from composite fillings have been identified. Among these, basic monomers and the so-called co-monomers are most often reported. The substances released from polymer-based materials demonstrate allergenic, cytotoxic, genotoxic, mutagenic, embryotoxic, teratogenic, and estrogenic properties. The aim of this study was to measure the amounts of triethylene glycol dimethacrylate (TEGDMA) and urethane dimethacrylate (UDMA) monomers released from composite dental fillings to citrate-phosphate buffer with the pH of 4, 6, 8 after 24 h and 6 months from the polymerization. Ten samples for each polymerization method had been made from the composite material (Filtek Supreme XT, 3M ESPE, St. Paul, USA), which underwent polymerization using the following lamps: halogen lamp (Translux CL, Heraeus Kulzer, Hanau, Germany) (sample H) and diode lamp (Elipar Freelight 2, 3M ESPE), with soft start function (group DS) and without that function (group DWS). It has been demonstrated that the type of light-curing units has a significant impact on the amount of TEGDMA and UDMA released. The amount of UDMA and TEGDMA monomers released from composite fillings differed significantly depending on the source of polymerization applied, as well as the pH of the solution and sample storage time. Elution of the monomers from composite material polymerized using halogen lamp was significantly greater as compared to curing with diode lamps.

Synthesis and Characteristics of Dental Composites with Novel Bis-GMA Derivate as a Resin Base

2,2-bis [4-(2-hydroxy-3-methacryloyloxypropoxy) pheny propane (Bis-GMA) and triethylene glycol dimethacrylate (TEGDMA) have been commonly used as a viscous monomer and a reactive diluent in the organic phase of dental restorative composites, respectively. The purpose of addition of TEGDMA is mainly to decrease the high viscosity of Bis-GMA caused by hydrogen bonding between hydroxyl groups. However, some adverse effects will accompany with increased amounts of the TEGDMA, such as higher values of polymerization shrinkage, which is not undesirable for the clinical application. Therefore, substituting hydroxyl groups of Bis-GMA might be an appropriate and effective way to reduce the amount of diluents and weaken the accompanied adverse effects. This work focuses on the synthesis of a novel Bis-GMA derivate, substituting acetyl groups for hydroxyl groups in Bis-GMA. The viscosity of Bis-GMA characterized with rotational rheometer was significantly decreased from 820 Pa.s to 11 Pa.s by substitution of acetyl group, leading to the low amount of TEGDMA in resin matrix. Differential Scanning Calorimeter (DSC) was used for investigating the reaction kinetics of this novel monomer with different mass ratios of TEGDMA. The results suggested that the maximum conversion of the Ac-Bis-GMA can reach 88% while the corresponding value for Bis-GMA is 75%. Dental composites were prepared from 2,2-bis [4-(2-acetyl-3-methacryloyloxypropoxy) pheny propane (Ac-Bis-GMA) or Bis-GMA resin mixtures with TEGDMA filled with 70 wt% silica co-fillers. The results presented that dental composites prepared from new resin matrixes exhibited adequate mechanical properties.

Degree of conversion and mechanical properties studies of UDMA based materials for producing dental posts

AbstractNanocomposites are a relatively new material in producing fiber re‐enforced dental posts. The mechanical properties of nanocomposites, which strongly associate with the resin matrix, nanoparticles, and the interface between inorganic fillers and organic matrix, play an important role in determining the quality of dental posts. This work was to investigate the effect of degree of conversion (DC) and silanization of fillers on the mechanical properties of nanocomposties. Experimental Urethane dimethacrylate (UDMA) based dental composites containing unsilanized and silanized SiO2 filler and various amount of triethylene glycol dimethacrylate (TEGDMA) were prepared at the first step. The DC of composites at different ratios of UDMA/TEGDMA, cure temperature and cure time was measured by Fourier transform infrared spectroscopy. The results showed that DC increases with the increase of TEGDMA content in resin matrix. Both increase of the cure temperature and cure time can cause the increase of DC. The incorporation of fillers, either silanized, or unsilanized filler, caused the decrease of DC. However, composites reinforced with silanized silica showed relatively lower DC, and DC decreased with the increase of silanized filler content. The effect of incorporation of fillers on the mechanical properties was investigated. Silanized silica can effectively improved the flexural strength and flexural modulus of material, and these properties increased with the increase of silica content. Thermomechanical analysis (DMA) provided the similar results to the static property measurements. SEM images of fracture surfaces of specimens from flexural testing revealed the surface morphology is strongly related to the quality of interface between inorganic fillers and organic matrix. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers

Light-cured or chemically cured orthodontic adhesive resins? A selection based on the degree of cure, monomer leaching, and cytotoxicity

The purpose of this study was to estimate the degree of cure and monomer leaching of a light-cured and a chemically cured (no-mix) adhesive and to assess their biologic properties. The degree of cure of adhesive specimens prepared with a procedure identical to the clinical bonding process was assessed by infrared spectroscopy. The adhesives were then immersed in normal saline solution for 2 months, and the residual monomer leached from the adhesives was quantitatively and qualitatively analyzed by liquid chromatography. The effect of the immersion media on human gingival fibroblasts' viability and proliferation was also evaluated with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and deoxyribonucleic acid (DNA) synthesis assays, respectively. The results were analyzed by analysis of variance and Tukey test (alpha = .05). No difference was found between the 2 adhesives with respect to their degree of cure and the amount of triethylene glycol dimethacrylate released; no diglycidyl dimethacrylate monomer was detected in the eluent. However, significant qualitative changes in the composition of the substances eluted from the 2 adhesives were observed. Whereas no cytotoxic effect was shown for either immersion media, a moderate reduction in the DNA synthesis was obtained by both adhesives, implying a minor cytostatic effect. Further research is required to assess the long-term biologic properties of adhesives, including potential estrogenic action.

Evaluation of the Length of Primary Chains in Cross-Linked Poly(methacrylate)s

Two series of cross-linked polymers were examined by equilibrium swelling: poly(methyl methacrylate) cross-linked with different amounts of triethylene glycol dimethacrylate and poly(urethane dimethacrylate)s derived from dicarbamates of oligoethylene glycols monomethacrylates and aromatic diisocyanates. The method of estimation of the length of primary chains has been proposed based on the full form of the Flory-Rehner equation. This required comparing the network parameter values obtained by swelling and those derived from some other sources. In some cases the results had no physical meaning, whereas in others they appeared to be consistent. The latter for poly(urethane dimethacrylate)s yielded the length of poly(methacrylate) primary chains in the range of two to eight, which seemed to be a reasonable result.

The in vitro cytotoxicity of eluates from dentin bonding resins and their effect on tyrosine phosphorylation of L929 cells

Objectives: The aim of this study was to examine the relationship between the monomers eluted from dentin-bonding systems and their cytotoxicities, and to investigate the biochemical effect of the monomers on tyrosine phosphorylation, especially relating to the cell growth activity, of L929 cells in vitro. Methods: The primers, uncured or cured adhesives (3M and Kuraray) were tested to determine the cytotoxicity of confluent L929 cells cultured by Eagle's MEM medium supplemented with 10% FCS. The area of cells affected by the eluted monomers were evaluated with an image analyzer and the concentrations of monomers eluted into the medium were measured with high performance liquid chromatography (HPLC) after 24 h incubation. The protein composition of the stimulated cells was compared by sodium dodecyl sulfate–polyacrylamide gel electrophoresis and tyrosine phosphorylation was detected by Western blot. Results: The primer and uncured adhesives revealed variable cytotoxicities. 2-hydroxyethyl-methacrylate (HEMA) was the major component eluted from uncured primers and adhesives. Small amounts of triethylene glycol dimethacrylate (TEGDMA) were also detected from the uncured adhesives. The cytotoxicities of the adhesives decreased as photo activation time increased. The amount of monomers eluted from the cured adhesives was almost undetectable and did not reach a sufficient concentration to suppress cell viability or cell growth. The cytotoxicities of the primers and adhesives correlated well with the amounts of either HEMA or TEGDMA eluted. Moreover, a high concentration of HEMA (4 mg/ml medium) affected intracellular tyrosine phosphorylation, which is related to cellular activities. Significance: Although the monomers present in dentin bonding resins are cytotoxic to L929 cells, the amount from cured bonding resin is very small and does not provide a cytotoxic dose. This data does however suggest that clinical exposure to the uncured primers and adhesives of dentin bonding resins should be minimized.

Degree of conversion of composites measured by DTA and FTIR

Objective. Differential thermal analysis (DTA) using a split fiber optic light source has been reported to be a convenient method of measuring the degree of conversion (DC) of light-activated composites. The purpose of this study was to compare the results by DTA and Fourier transformation infrared spectroscopy (FTIR), and evaluate the usefulness of the DTA method. Methods. Experimental 2,2-bis[4-(3-methacryloyloxy-2-hydroxypropoxy)phenyl]propane-based composites containing SiO 2 filler and various amounts of triethyleneglycol dimethacrylate (TEGDMA) were prepared, and the DC of each composite was determined by DTA or FTIR with 60 s irradiation. The DC of three proprietary composites containing hybrid filler or prepolymerized resin filler were also measured by both methods with 20 or 60 s irradiation. The results were analyzed by ANOVA and Fisher's protected least significant difference test. Results. By both DTA and FTIR, the DC of experimental composites increased as the proportion of TEGDMA increased, although DTA showed 3–10% greater values ( p<0.05) than FTIR. For proprietary composites that contain hybrid filler, the values by DTA were not significantly different from those by FTIR at 20 s exposure. Longer irradiation time resulted in greater DC ( p<0.05) for both methods, and DTA showed 5–7% greater values than FTIR. However, the DC of the composite containing prepolymerized resin filler was 30% less by FTIR than by DTA, possibly due to the influence of unpolymerized species in the filler. Significance. The DC values determined by DTA and FTIR showed good agreement for most materials including model composites. In addition, DTA may be more useful than FTIR to measure the DC of composites containing prepolymerized resin filler.

Mechanical and thermal behavior of cotton cellulose graft‐copolymerized using hydroxyethyl methacrylate in presence of triethylene glycol dimethacrylate

AbstractUV‐radiation‐induced graft‐copolymerization of cotton cellulose was carried out with 2‐hydroxyethyl methacrylate (HEMA) in the presence of small amounts of triethylene glycol dimethacrylate (TEGDMA) using benzoin ethyl ether (BEE), uranyl nitrate (UN), and ceric ammonium nitrate (CAN) as photoinitiators. The presence of very small amounts of (TEGDMA) in the HEMA grafting bath led to great enhancement in the graft add‐on as compared to that obtained on the sodium hydroxide‐preswollen substrate. With increase in the graft add‐on, the breaking load of cotton decreased, whereas its thermal stability improved © 1993 John Wiley &amp; Sons, Inc.