Posts Tagged ‘bisGMA’

PRODUCT SPOTLIGHT: bisGMA

Wednesday, July 31st, 2013
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BisGMA, X-950-0000

Item Code: X-950-0000
Product Name: Bisphenol A Glycidyl Methacrylate, BisGMA, Bisphenol A glycerolate dimethacrylate, Bisphenol”A”-bis-(2-hydroxypropyl)methacrylate, Bis-GMA
CAS#: 1565-94-2
INCI: Isopropylidenediphenyl Bisoxyhydroxypropyl Methacrylate

Bisphenol A Glycidyl Methacrylate, or bis-GMA is a high viscosity resin that has been used in dental formulations for years. Our bis GMA is manufactured with low levels of BPA or bisphenol A and low color. 

Performance Properties:

  • High Viscosity
  • Low color
  • Dilutes easily in typical solvents and diluents

Typical Applications:

  • Dental composite base resin
  • Core resin for “sculpting” nail gels
  • Promotes adhesion to fingernails

 

**** Contact Us FOR MORE INFORMATION OR SAMPLES! ****

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TPO Evaluated in Dental Composites

Monday, January 9th, 2012
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Curing efficiency of dental resin composites formulated with camphorquinone or trimethylbenzoyl-diphenyl-phosphine oxide

Luis Felipe J. Schneider, Larissa Maria Cavalcante, Scott A. Prah, Carmem S. Pfeifer, Jack L. Ferracane.  “Curing efficiency of dental resin composites formulated with camphorquinone or trimethylbenzoyl-diphenyl-phosphine oxide” Dental Materials.  December 2011:  Online

Summary:

This research presents trimethylbenzoyl-diphenyl-phosphine oxide (TPO) as an alternative to camphorquinone (CQ) photoinitiator systems for dental resins.  An immediate advantage is the low color of TPO in comparison to the strong yellow color of CQ. Testing using a spectrophotometer and differential scanning calorimetry (DSC) revealed that TPO had higher reactivity than CQ.  CQ exhibited higher absorbed power density, (PDabs) and better depth of cure.

Materials

Testing of each photoinitiator was performed using 50:50 formulations of 2,2-bis[4-2(2-hydroxy-3-
methacroyloxypropoxy)phenyl]propane (Bis-GMA, Esstech) and triethyleneglycol dimethacrylate (TEGDMA, Esstech).


LINK:  http://dx.doi.org/10.1016/j.dental.2011.11.014

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Optimized LED cure of BisGMA:TEGDMA

Thursday, December 1st, 2011
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Micro-Raman spectroscopic analysis of the degree of conversion of composite resins containing different initiators cured by polywave or monowave LED units

Vesna Miletic a, Ario Santini b,

a Clinical Lecturer, University of Belgrade, School of Dentistry, Department of Restorative Odontology and Endodontics, Rankeova 4, Belgrade, Serbia

b Director of Biomaterials Research, The University of Edinburgh, Edinburgh Postgraduate Dental Institute, Lauriston Place, Edinburgh EH3 9HA, United Kingdom

Received 20 August 2011; revised 28 October 2011; Accepted 30 October 2011. Available online 6 November 2011.

Objectives

To determine the degree of conversion (DC) over 48 h post-curing of resin mixtures containing trimethylbenzoyl-diphenylphosphine oxide (TPO) initiator cured by a polywave or a monowave LED light-curing unit (LCU).

Methods

In resin mixtures based on equal weight percent (wt%) of BisGMA and TEGDMA the following initiators were added: 0.2wt% camphorquinone (CQ) + 0.8wt% ethyl-4-dimethylaminobenzoate (EDMAB) (Group 1); 1wt% TPO (Group 2) and 0.1wt% CQ + 0.4wt% EDMAB + 0.5wt% TPO (Group 3). Half of the samples in each group (n = 5) were cured using a polywave (bluephase® G2, Ivoclar Vivadent) or a monowave LED LCU (bluephase®, Ivoclar Vivadent). The DC was measured using micro-Raman spectroscopy within 5 min and then 1, 3, 6, 24 and 48 h post-irradiation. The data were analyzed using general linear model and two-way ANOVA for the factors ‘time’, ‘material’, ‘surface’ and ‘LCU’ at α=0.05.

Results

The initial DC values obtained upon light curing remained similar over a 48 h period. bluephase® G2 produced the highest DC in Group 2 followed by Group 3, and Group 1. bluephase® resulted in the highest DC in Group 1, followed by Group 2 and Group 3 (p < 0.05).

Conclusions

Unfilled resin materials containing both TPO- and CQ-amine initiators are effectively cured using bluephase® G2. Resin mixture with the same wt% of initiators is better cured when TPO is the only initiator, compared to CQ-amine only or combined TPO and CQ-amine system. After initial light cure, no additional conversion of uncured monomers was detected in an unfilled resin material over 48 h at 37 °C.

Materials

Page 5 of 24 Ac ce pte d M an usc rip t 4 Materials and Methods The following materials were
used in the study: bisphenol A bis(2-bydroxy-3- methacryloxypropyl)ether (BisGMA), triethylene
glycol dimethacrylate (TEGDMA)
, camphorquinone (CQ) (Esstech Inc, Essington, PA


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Esstech Resins in Antibacterial Nanocomposite

Monday, July 11th, 2011
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Development of an antimicrobial resin—A pilot study

Catherine Fan, Lianrui Chu, H. Ralph Rawls, Barry K. Norling, Hector L. Cardenas, Kyumin Whang

Dental Materials.  Volume 27, Issue 4, Pages 322-328 (April 2011)

Summary

To demonstrate that silver nanoparticles (AgNPs) could be synthesized in situ in acrylic dental resins.

Methods: Light-cure (LC; bisphenol A glycidyl methacrylate, tetraethyleneglycol dimethacrylate, bisphenol A ethoxylate dimethacrylate blend) and chemical-cure systems (CC; orthodontic denture resin) were used to synthesize AgNPs using different concentrations of Ag benzoate (AgBz).

Results: Rockwell hardness for LC resins showed that resins could be cured with up to 0.15% AgBz, while the hardness of CC resins were unaffected in the concentrations tested. UV–Vis spectroscopy and transmission electron microscopy confirmed the presence of AgNPs in both LC and CC resins. Generally, CC resins had better distribution of and much smaller AgNPs as compared to LC resins overall. In some samples, especially in LC resins, nanoclusters were visible. An in vitro release study over four-weeks showed that CC resins released the most Ag+ ions, with release detected in all samples. However, LC resins only released Ag+ ions when AgBz concentration was greater than 0.1% (w/w). AgNP-loaded CC resins made with 0.2 and 0.5% (w/w) AgBz were tested for antibacterial activity in vitro against Streptococcus mutans, and results showed 52.4% and a 97.5% bacterial inhibition, respectively. Further work is now warranted to test mechanical properties and to optimize the initiator system to produce commercially useful dental and medical resins.

Significance:  Success in this work could lead to a series of antimicrobial medical and dental biomaterials that can prevent secondary caries and infection of implants.


LINK:  http://www.demajournal.com/article/S0109-5641%2810%2900475-6/abstract


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Reduced Shrinkage Stress with Optimized BisGMA/TEGDMA Ratios

Thursday, May 5th, 2011
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BisGMA/TEGDMA ratio and filler content effects on shrinkage stress

Flávia Gonçalve, Caio L.N. Azevedo, Jack L. Ferracane,Roberto R. Braga
Dental Materials, Volume 27, Issue 6, Pages 520-526 (June 2011)

Abstract

Objective

To investigate the contributions of BisGMA:TEGDMA and filler content on polymerization stress, along with the influence of variables associated with stress development, namely, degree of conversion, reaction rate, shrinkage, elastic modulus and loss tangent for a series of experimental dental composites.

Methods

Twenty formulations with BisGMA:TEGDMA ratios of 3:7, 4:6, 5:5, 6:4 and 7:3 and barium glass filler levels of 40, 50, 60 or 70wt% were studied. Polymerization stress was determined in a tensilometer, inserting the composite between acrylic rods fixed to clamps of a universal test machine and dividing the maximum load recorded by the rods cross-sectional area. Conversion and reaction rate were determined by infra-red spectroscopy. Shrinkage was measured by mercury dilatometer. Modulus was obtained by three-point bending. Loss tangent was determined by dynamic nanoindentation. Regression analyses were performed to estimate the effect of organic and inorganic contents on each studied variable, while a stepwise forward regression identified significant variables for polymerization stress.

Results

All variables showed dependence on inorganic concentration and monomeric content. The resin matrix showed a stronger influence on polymerization stress, conversion and reaction rate, whereas filler fraction showed a stronger influence on shrinkage, modulus and loss tangent. Shrinkage and conversion were significantly related to polymerization stress.

Significance

Both the inorganic filler concentration and monomeric content affect polymerization stress, but the stronger influence of the resin matrix suggests that it may be possible to reduce stress by modifying resin composition without sacrificing filler content. The main challenge is to develop formulations with low shrinkage without sacrificing degree of conversion.

LINK:  http://www.demajournal.com/article/S0109-5641%2811%2900020-0/abstract


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BisGMA – UDMA Composite with Nanosilica Fibers

Tuesday, March 29th, 2011
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Synthesis of Nanosilica Fillers for Experimental Dental Nanocomposites and Their Characterisations
Tuan Noraihan Azila Tuan Rahim1, Dasmawati Mohamad1*, Abdul Rashid Ismail1 and Hazizan Md Akil2

1School of Dental Sciences, Universiti Sains Malaysia,
2School of Material and Mineral Resources Engineering, Universiti Sains Malaysia

MATERIALS:

Tetraethyorthosilicate (TEOS), absolute ethanol, ammonia,  γ-methacryloxypropyl-trimethoxysilane (γ-MPS), acetic acid (CH3COOH), bisphenol A glycidyl methacrylate (BisGMA, Esstech), diurethane dimethacrylate (UDMA), triethylene glycol dimethacrylate (TEGDMA), camphorquinone (CQ), (2-dimethylaminoethyl) methacrylate (DMAEMA) and distilled water were used in this work. The chemicals were employed without any further purification.

ABSTRACT:

The aim of this study was to synthesise nanosilica fillers for use in the fabrication of experimental dental nanocomposites and to evaluate their properties,  including surface and mechanical properties. Monodispersed, spherical silica nanoparticles were synthesised via a sol-gel process, and a size range of 10–20 nm was obtained. Surface treatment of the nanosilica was carried out with the silane coupling agent γ-methacryloxypropyltrimethoxysilane (MPS) to reduce agglomeration of nanosilica. Experimental dental nanocomposites with two different filler contents, 30 and 35 wt%, were fabricated and polymerised with a light curing unit for 40 s. The surface morphology, surface roughness, flexural strength and elastic modulus were evaluated and compared. A nanocomposite with 35% filler content showed higher filler compaction, lower surface roughness and higher elastic modulus than a nanocomposite filled with 30% filler. However, the nanocomposite filled with 30% filler content showed higher flexural strength. Based on the results obtained, the synthesised nanosilica is a promising material for the fabrication of dental nanocomposites for tooth-filling applications.



LINK:  http://web.usm.my/jps/22-1-11/22.1.6.pdf


Journal of Physical Science, Vol. 22(1), 93–105, 2011
© Penerbit Universiti Sains Malaysia, 2011

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Properties of UDMA and Bis-GMA based Composites

Monday, February 28th, 2011
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Hydrogen bonding interactions in methacrylate monomers and polymers

Marianela T. Lemon, Melissa S. Jones, Jeffrey W. Stansbury
Department of Craniofacial Biology, University of Colorado School of Dentistry, Aurora, Colorado 80045

ABSTRACT

It is well appreciated that hydrogen bonding affects a variety of monomer and polymer properties. This study focused on Bis-GMA and urethane dimethacrylate (UDMA) to help elucidate how the strength and nature of
specific noncovalent interactions involved with these different functional dimethacrylate structures are expressed in the monomers and polymers. Hydrogen bonding interactions in monomers and comonomer mixtures as well as in appropriate model compounds were examined by FT-IR under ambient conditions, at elevated temperatures and in dilution studies. The investigation of hydrogen bonding extended to monomer viscosity, photopolymerization reaction kinetics, and polymer mechanical properties.

CONCLUSION

The strength of hydrogen bonding was shown not only to be greater for Bis-GMA compared with UDMA, but there is also greater contribution from intermolecular interactions that enhance the hydrogen bonding effects. While UDMA-based polymers reach significantly higher levels of conversion compared with Bis-GMA materials, the stronger hydrogen bonding reinforcement associated with Bis-GMA appears to provide for comparable mechanical strength properties. Depending on the hydrogen bond donor functionality of a monomer as well as its neighboring functional groups, overall monomer structure and comonomers used, hydrogen bonding can favorably affect polymerization reactivity and mechanical properties, even in materials that form highly crosslinked polymeric networks.


Wiley Periodicals, Inc. J Biomed Mater Res 83A: 734–746,2007

Link:  http://onlinelibrary.wiley.com/doi/10.1002/jbm.a.31448/abstract



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PMGDM / UDMA Used in Remineralization Applications

Friday, September 10th, 2010
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Effects of adhesive, base and diluent monomers on water sorption and conversion of experimental resins

Sabine H. Dickens, Glenn M. Flaim, Cynthia J.E. Floyd

Dental Materials Volume 26, Issue 7, Pages 675-681 (July 2010)

Objectives: To establish the relationship of resin composition and resin hydrophilicity (indicated by solubility parameters and logP) to water sorption (WS), solubility, and degree of double bond conversion (DC) of resin mixtures designed for adhesive restoratives by varying the concentration of pyromellitic glycerol dimethacrylate (PMGDM) and various co-monomers.

Methods: Sixteen resin mixtures were prepared with (30–70) mass fraction % PMGDM. At given PMGDM concentrations there were up to five compositions with increasing logP. Polymer disks (13mm×0.7mm) were exposed to 96% relative humidity (RH) to determine water sorption in humid atmosphere (WSH) and subsequently immersed in water for immersion water sorption (WSI) and solubility. DC was assessed by near infrared spectroscopy.

Results: WSI was somewhat higher than WSH, which ranged from (2.1 to 5.3) mass fraction %. Both data were positively correlated to PMGDM concentrations [Pearson correlation, p<0.02; R2=0.74, 0.73 (WSI)] and solubility (R2=0.64), but not to logP. When grouped by structural similarities, i.e., base resins with bisphenol A core (Group B), Group O containing diluent monomers, or Group U containing urethane dimethacrylate, WS within each group was inversely correlated to logP with R2=0.98, 0.81, 0.95, and WS/solubility correlation improved with R2=0.88, 0.92 and 0.75, respectively. Solubility ranging from 0.3% to 2.3% was inversely related to DC (r=−0.872). Conversion ranging from 41% to 81% was lower for resins with high base monomer concentrations and highest in mixtures with UDMA.

Significance: LogP was a good predictor of WS after grouping the resins according to functional, compositional and structural similarities. WS and conversion were reasonably well predicted from Hoy’s solubility parameters and other physical resin properties.

Link:  http://www.demajournal.com/article/S0109-5641%2810%2900066-7/abstract


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Effect of Varying Filler Content in BisGMA:TEGDMA Composites

Friday, September 10th, 2010
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Contraction stress related to composite inorganic content

F. Gonçalvesa, Y. Kawanob, R.R. Bragaa

Dental Materials Volume 26, Issue 7, Pages 704-709 (July 2010).

Objectives: The role of inorganic content on physical properties of resin composites is well known. However, its influence on polymerization stress development has not been established. The aim of this investigation was to evaluate the influence of inorganic fraction on polymerization stress and its determinants, namely, volumetric shrinkage, elastic modulus and degree of conversion.

Methods: Eight experimental composites containing 1:1 BisGMA (bisphenylglycidyl dimethacrylate):TEGDMA (triethylene glycol dimethacrylate) (in mol) and barium glass at increasing concentrations from 25 to 60vol.% (5% increments) were tested. Stress was determined in a universal test machine using acrylic as bonding substrate. Nominal polymerization stress was obtained diving the maximum load by the cross-surface area. Shrinkage was measured using a water picnometer. Elastic modulus was obtained by three-point flexural test. Degree of conversion was determined by FT-Raman spectroscopy.

Results: Polymerization stress and shrinkage showed inverse relationships with filler content (R2=0.965 and R2=0.966, respectively). Elastic modulus presented a direct correlation with inorganic content (R2=0.984). Degree of conversion did not vary significantly. Polymerization stress showed a strong direct correlation with shrinkage (R2=0.982) and inverse with elastic modulus (R2=0.966).

Significance: High inorganic contents were associated with low polymerization stress values, which can be explained by the reduced volumetric shrinkage presented by heavily filled composites.

Link:  http://www.demajournal.com/article/PIIS0109564110000801/fulltext


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Alternative Photoinitiator Assists in Camphorquinone Cure

Tuesday, July 27th, 2010
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Degree of conversion and color stability of the light curing resin with new photoinitiator systems

Dong-Hoon Shin, H. Ralph Rawls

Dental Materials, August 2009 (Vol. 25, Issue 8, Pages 1030-1038)

Objectives: This study investigated p-octyloxy-phenyl-phenyl iodonium hexafluoroantimonate (OPPI) as a photoinitiator, in combination with camphorquinone/amine photoinitiation systems, for use with di(meth)acrylate-based composite resins. The investigation determined if the inclusion of OPPI improved degree and rate of conversion, initial color and color stability of a representative composite resin dental material.

Methods: Camphorquinone (CQ) and OPPI were combined in various proportions with the amine co-initiator 2-dimethylaminoethyl methacrylate (DMAEMA) and used at two levels in which CQ+OPPI+DMAEMA=1wt.% or 3wt.% to photoinitiate a BisGMA/BisEMA/TEGDMA (37.5:37.5:25wt.%) monomer blend. Monomer mixture (GTE) was made by mixing 37.5wt.% BISGMA (lot # 568-21-07, ESSTECH, Essington, PA), 37.5wt.% BISEMA (lot # 474-32-02, ESSTECH), and 25wt.% TEGDMA (lot # 597-23-02, ESSTECH). A total of eight groups (four groups for each level of total photoinitiator, 1% and 3%) were tested according to the following proportion of components in the photoinitiator system: Each monomer was polymerized using a quartz-halogen curing unit (Demetron 400, Demetron Research Corp., Danbury, CT) with an intensity of 400mW/cm2 for 5s, 20s, 40s, 60s, 300s and their conversion levels (DC) were determined at each exposure time using a Fourier transform infrared spectrophotometer (FTIR). To examine color stability, experimental composite resins were made by mixing 3.2% silanated barium glass (78wt.%, average filler size; 1μm) with each monomer system, except both CQ only group and 1% CO group, which were found to cure insufficiently to be able to prepare useful specimens. Disk-shaped samples (10mm in diameter and 1.5mm in thickness) were made and stored under the conditions of dry or saline solution at room temperature (25°C) or 60°C water bath. Each CIELAB scale was determined with a colorimeter (CHROMA METER CR-400) at the time of baseline (day after curing), 1 week, 2 weeks, and 4 weeks later.

Results: The high level (3%) photoinitiated groups exhibited greater DC than the low level (1%) groups. In the 3% group, the COA group showed the fastest and the highest DC, while in the 1% group the CA and COA groups showed the greatest DC. In the color stability test, both CA groups were darker and more yellow than the CO and COA groups. Color was more stable in composite resins containing OPPI than those containing only the CQ and amine components. The least color change (greatest color stability) was found using 25°C saline solution aging, and the most change (least color stability) occurred using 60°C dry air aging.

Significance: This study suggests that OPPI can be used to replace the amine in a given CQ/amine photoinitiator system to accelerate cure rate, increase conversion, reduce initial color and increase color stability.

Link: http://www.demajournal.com/article/S0109-5641%2809%2900139-0/abstract


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