Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ACRYLATES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 361 records · Page 20Linked to original sources
PubMed1978

Wear of combinations of acrylic resin and porcelain, on an abrasion testing machine.

Wear tests of various combinations of acrylic resin and porcelain were made using a machine which was designed to test materials under conditions similar to those of masticatory function by simulating the loads, sliding distances, and contact times encountered in the human masticatory cycle. The results showed that the amount of wear of the two materials worn in combination depended on the nature of the surrounding medium and on the surface roughness of the opposing material. Acrylic resin showed good wear resistance provided no third party abrasive or opposing hard, rough surface was present. When a mild abrasive was incorporated in the system, the acrylic resin vs acrylic resin combination wore almost seven times more than porcelain vs porcelain. Clinical experience would suggest that this is a reasonably sound order of wear.

Acrylic Resins↗
PubMed1993

Comparison of two different silane compounds used for improving adhesion between fibres and acrylic denture base material.

This study was aimed at clarifying the effects of two different silane compounds on the adhesion between the different fibres and acrylic resin. The fibres used as reinforcement in the acrylic resin test specimens were glass, carbon and aramid fibres and the silane treated and untreated versions of each type of the fibres were tested. The fracture resistance of the test specimens were assessed and the fibres were studied by a scanning electron microscope (SEM) to establish the adhesion between the fibres and acrylic resin. The results showed that silanization of glass and aramid fibres enhances the adhesion between the fibres and acrylic resin. The findings were confirmed by the SEM photographs taken. The use of a scanning electron microscope proved to be useful for the investigation of the adhesive properties of the materials used.

Acrylic Resins↗
PubMed1995

The effect of void space and polymerization time on transverse strength of acrylic-glass fibre composite.

The aim of this study was to establish (i) the causes and effects of void space formation in acrylic-glass fibre composite material; and (ii) to clarify the effect of polymerization time of acrylic resin on the transverse strength of heat-cured acrylic resin test specimens. In study 1, three transverse sections of the continuous glass fibre reinforced test specimens (n = 48) were studied by a scanning electron microscope (SEM) and the SEM-micrographs were analysed by a computerized picture analyser. The results suggested that the void space inside the test specimens is caused by a lack of the adsorbed monomer liquid in the fibre bundle before polymerization. The correlation coefficient between these two factors was -0.633 (P < 0.001). No correlation was found between the void space of the acrylic-glass fibre composite and the transverse strength of the test specimens (r = 0.000, P = 1.000). The results of study 2 showed that the transverse strengths of test specimens (n = 240, total) subjected to polymerization of different time spans did not vary significantly (P > 0.05).

Acrylic Resins↗
PubMed2004

Shear bond strength of microwaveable acrylic resin for denture repair.

Microwaveable acrylic denture resins are believed to provide an effective means of repairing fractured dentures. This in vitro investigation compared the bond strength of a microwaveable acrylic resin as a denture repair material to two established auto-polymerized resins. Fifty-one specimens were made using Lucitone 199 as a simulated denture base, and were then divided into three groups of 17 samples each. Each test group was bonded with the following acrylic resins: Acron Mc, Rapid Repair and Palapress. A shear bond strength test was carried out 24 h after the samples were bonded. Fracture analysis showed that bond failure was adhesive for all groups. Shear bond values showed a statistically significant difference at P < 0.05 level between Acron Mc and Rapid Repair; Palapress and Rapid Repair, and indicated that Acron Mc and Palapress were superior to Rapid Repair as a repair material. However, there was no statistical difference found between Acron Mc and Palapress. Microwaveable acrylic resins produce repaired junctions of adequate strength.

Acrylic Resins↗
PubMed1982

Concomitant sensitization to hydroquinone and P-methyoxyphenol in the guinea pig; inhibitors in acrylic monomers.

Concomitant sensitization to hydroquinone and p-methoxyphenol occurred in sensitization experiments with acrylic monomers in guinea pigs. No relation between the concentration of the inhibitor in the monomers and the incidence of these concomitant sensitizations could be detected. Concomitant sensitization did not influence the cross reaction pattern of the acrylic monomers. The sensitizing potential of acrylic monomers is not influenced by the inhibitors, but some acrylic monomers seem to interfere with the sensitizing potential of the inhibitors.

Acrylates↗
PubMed1983

The sensitizing potential of 2-ethylhexyl acrylate in the guinea pig.

The sensitizing potential of 2-ethylhexyl acrylate in the guinea pig could be demonstrated by Freund's Complete Adjuvant Test. This acrylate ester is a common constituent of adhesive tape. Allergic reactions to several brands of adhesive tape were not observed in 2-ethylhexyl acrylate sensitized animals. Cross reactions with other acrylic monomers were observed.

Acrylates↗
PubMed1984

Sensitizing potential of urethane (meth)acrylates in the guinea pig.

Urethane (meth)acrylates are used as prepolymers in ultraviolet-curable inks, varnishes and coating formulations for industrial purposes as well as resins for dental applications. The sensitizing capacity of 3 commonly used urethane (meth)acrylates was investigated using the guinea pig maximization test. The study shows that an aliphatic urethane acrylate is not only a more potent sensitizer than an aromatic one, but also more sensitizing than a (meth)acrylated aliphatic urethane.

Acrylates↗
PubMed1996

Occupational allergic contact dermatitis due to acrylates in Lodz.

Among 1619 patients suspected of occupational contact dermatitis examined during the years 1990-1994, sensitivity to acrylates was diagnosed in 9 persons (4 dental technicians, 4 dentists, 1 textile printer). Ethyleneglycol dimethacrylate (5 positive patch tests), methyl methacrylate (4), 2-hydroxyethyl methacrylate (4) and triethyleneglycol dimethacrylate (4) were the most common sensitizers. Comparison of patch test results in dental technicians and dentists indicated that dentists were sensitive to a greater number of (meth)acrylate (acrylate and methacrylate) allergens and also to certain other allergens (metals and rubber additives). Dental technicians were sensitive almost exclusively to methacrylates, while the textile printer only to acrylates.

Acrylates↗
PubMed1989

Chelation in metal intoxication XXX: Alpha-mercapto-beta-aryl acrylic acids as antidotes to cadmium toxicity.

alpha-Mercapto-beta-(2-furyl) acrylic acid (MFA), alpha-mercapto-beta-(2-hydroxyphenyl) acrylic acid (MHA), beta-1,2-phenylene di-alpha-mercaptoacrylic acid (1,2-PDMA) and beta-1,4-phenylene di-alpha-mercapto acrylic acid (1,4-PDMA) were compared to sodium N-benzyl-D-glucamine dithiocarbamate (NBG-DTC) an effective cadmium chelator, for their ability to mobilize Cd and influence the Cd induced tissue metallothionein (MT) in rats administered 109CdCl2, 72 hr earlier. MFA was almost as effective as NBG-DTC but more effective than MHA in enhancing urinary and faecal excretion of Cd, reducing tissue and blood levels of Cd and in lowering Cd induced increase in hepatic and renal MT contents. 1,2-PDMA and 1,4-PDMA were effective only in reducing the hepatic burden of Cd. The resuls do not indicate any direct relationship between the efficacy of alpha-mercapto-beta-aryl acrylic acids to decorporate body Cd and their lipophilic-hydrophilic character or number-arrangement of their sulfhydryl groups.

Acrylates↗
PubMed1996

The effect of oral commensal bacteria on candidal adhesion to denture acrylic surfaces. An in vitro study.

The effect of four different species of oral bacteria (Streptococci (X 2); Escherichia; Porphyromonas) on the adhesion of Candida albicans and Candida krusei to denture acrylic surfaces was studied using a previously described in vitro adhesion assay. Clear acrylic strips immersed in known concentrations of bacterial suspensions and incubated for 45 min to 1 h, at 37 degrees C, were transferred to yeast suspensions of known concentrations and incubated for a similar period, and the adherent yeasts were quantified using an image analysis system. Pre-exposure to different bacterial concentrations resulted in suppression of candidal adhesion to varying degrees. Of three selected concentrations, exposure to the highest bacterial concentration (10(6) organisms/ml) resulted in a consistent reduction in candidal adhesion, except for E. coli-C. albicans and S. salivarius-C. albicans combinations. Candidal adhesion was significantly reduced on pre-exposure to S. sanguis and P. gingivalis, but not E. coli. There were also significant differences in relative adhesion between C. albicans and C. krusei. Taken together, these results indicate that the adhesion of yeasts to acrylic strips is modulated both by the quantity and the quality of pre-existing bacterial flora on acrylic surfaces.

Acrylic Resins↗
PubMed2006

In vitro antiseptic properties of an ammonium compound combined with denture base acrylic resin.

BACKGROUND: Denture base acrylic resin is easily colonised by oral endogenous bacteria and Candida spp., and eventually by extra-oral species such as Staphylococcus spp., Pseudomonadaceae or members of Enterobacteriaceae. This microbial reservoir can be responsive for denture related stomatitis and aspiration pneumonia, a life-threatening infection especially in geriatric patients. However, the oral and denture hygiene of dependent elderly individuals is extremely poor. OBJECTIVE: This in vitro study aimed to determine the per cent of a quaternary ammonium compound heat-polymerised in acrylic resin necessary to obtain denture base displaying antiseptic properties. DESIGN: Acrylic resin discs containing 2-50% ammonium polymer (Poly 202063A; 0% control) were soaked in artificial saliva for 4 weeks. Resin discs were incubated for 24 hours with Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa [37 degrees C, brain-heart infusion (BHI) broth and phosphate-buffered saline (PBS) buffer] and Candida albicans (30 degrees C, Schaedler broth), in 15 ml (168 discs) and 600 microl (168 discs) of inoculum. Microbial growth was verified at t 0 hours and t 24 hours. Data were recorded as the mean of three colony forming unit (CFU) numerations. The borderline of antimicrobial effect was determined at 0.1% viable cells. RESULTS: In 600 microl of PBS inoculum, resin specimens had a bactericidal effect (E. coli and S. aureus: 2%; P. aeruginosa: 10%) and a fungicidal effect (C. albicans: 50%). Long-term stability and toxicity in vivo studies are now required. CONCLUSION: A 2% quaternary ammonium compound polymerised with a denture acrylic resin displayed antiseptic properties after a 4-week soaking period in artificial saliva. Such antiseptic denture base could help geriatric patients to improve their oral health.

Acrylic Resins↗
PubMed1999

Dosimetric characteristics of acrylic and stainless steel cones for electron beam therapy.

Dosimetric characteristics of acrylic and stainless steel cones for electron beam therapy were investigated. Acrylic and stainless steel cylindrical cones of 6, 7, and 8 cm in diameter and electron beams of energies 6, 9, 12, 15, 18, and 21 MeV were used for the measurements. Both acrylic and stainless steel cones showed high dose areas along the rim. The dose along the rim grew with increasing electron beam energy. The highest dose along the rim was 115% of the maximum dose on a central axis when a 6-cm-diameter acrylic cone and 21-MeV electrons were combined.

Acrylates↗
PubMed2006

Synthetic consolidants attacked by melanin-producing fungi: case study of the biodeterioration of Milan (Italy) cathedral marble treated with acrylics.

Monuments and artistic stone surfaces are often consolidated and protected with synthetic polymers, in particular, acrylics. Although it is generally thought that acrylic polymers are resistant to biodeterioration, we report for the first time the systematic occurrence of dematiaceous meristematic fungi on many marble samples of the cathedral in Milan (Italy) previously treated with this material. Fourier transform infrared spectroscopy applied to the Milan cathedral stone samples revealed characteristic features of biodeteriorated synthetic resins that differentiated them from the aged but nonbiodeteriorated samples. Samples showing biological colonization were analyzed for the presence of fungi. Cultivation and morphological characterization and methods independent from cultivation, such as denaturing gradient gel electrophoresis coupled with partial 18S rRNA gene sequencing and immunofluorescence staining with melanin-binding antibodies, showed that melanin-producing species are heavily present on stone surfaces protected with acrylic resins. This observation raises the question of the effectiveness of acrylics in protecting stone artworks.

Acrylic Resins↗
PubMed1993

Degradation of a sodium acrylate oligomer by an Arthrobacter sp.

Arthrobacter sp. strain NO-18 was first isolated from soil as a bacterium which could degrade the sodium acrylate oligomer and utilize it as the sole source of carbon. When 0.2% (wt/wt) oligomer was added to the culture medium, the acrylate oligomer was found to be degraded by 70 to 80% in 2 weeks, using gel permeation chromatography. To determine the maximum molecular weight for biodegradation, the degradation test was done with the hexamer, heptamer, and octamer, which were separated from the oligomer mixture by fractional gel permeation chromatography. The hexamer and heptamer were consumed to the extents of 58 and 36%, respectively, in 2 weeks, but the octamer was not degraded. Oligomers with three different terminal groups were synthesized to examine the effect of the different terminal groups on biodegradation, but few differences were found. Arthrobacter sp. NO-18 assimilated acrylic acid, propionic acid, glutaric acid, 2-methylglutaric acid, and 1,3,5-pentanetricarboxylic acid. Degradation of the acrylic unit structure by this strain is discussed.

Acrylates↗
PubMed1998

Sensitization and development of allergic contact dermatitis caused by a single contact with an electrosurgical grounding plate containing acrylates.

Acrylates are known as potent sensitizers which can cause sensitization even during patch testing. A single exposure to concentrated acrylates can induce primary sensitization and contact dermatitis. Here we describe a 50-year-old man who developed contact dermatitis at the site of an electrosurgical grounding plate 2 weeks after orthopedic surgery. Patch testing revealed positive reactions to the electrosurgical plate and its components hydroxyethyl acrylate and hydroxyethyl methacrylate. As the patient has never had contact with acrylate-containing materials before, there is a high probability of primary sensitization by a single contact with the grounding plate during surgery.

Acrylates↗
PubMed2005

Optical coherence tomography of intraocular lens implants and their relationship to the posterior capsule: a pilot study comparing a hydrophobic acrylic to a plate-haptic silicone type.

BACKGROUND: Optical coherence tomography (OCT) has been used to examine the anterior as well as the posterior segment and can be used to examine the intraocular lens (IOL) and their relationship to the posterior capsule in vivo. OBJECTIVES: To use OCT to examine two of the IOLs and some of the features related to the development of posterior capsular opacification (PCO). METHODS: This is a pilot study of a prospective (n = 12) and a retrospective (n = 14) series of patients who had uneventful phacoemulsification and IOL implantation of either hydrophobic acrylic (Acrysof; Alcon) or plate-haptic (PH) silicone (C11UB; Chiron, Bausch & Lomb) IOLs. The outcome of interest was the ability of OCT to clearly delineate the outline of the IOL optics and their appositional relationship to the posterior capsule. RESULTS: OCT showed that hydrophobic acrylic IOLs had a better defined outline than PH silicone IOLs. It also showed close apposition between hydrophobic acrylic optics and the mid-peripheral part of the posterior capsule and the absence thereof with PH silicone IOLs. CONCLUSIONS: Hydrophobic acrylic implants have better definition on the OCT scans than PH silicone and they develop close apposition to the posterior capsule. The latter feature is consistent with the 'no space, no cell, no PCO' concept and what is known about the effect of the implant material and design on the rate of PCO.

Acrylic Resins↗
PubMed2004

Application of poly(acrylic acid) superporous hydrogel microparticles as a super-disintegrant in fast-disintegrating tablets.

Poly(acrylic acid) superporous hydrogel (SPH) microparticles possessing a unique porous structure were used as a wicking agent to decrease disintegration time of fast-disintegrating tablets (FDTs). The compression behaviour of poly(acrylic acid) SPH microparticles was evaluated using the Kawakita equation. Effects of various SPH microparticle sizes and a 19-run fractional factorial design were evaluated. The factorial design was based on four factors consisting of ketoprofen, SPH microparticle, filler, and tableting pressure, and each factor contained three levels on the disintegration time and tensile strength of the prepared FDTs. The poly(acrylic acid) SPH microparticles existed in an amorphous state and swelled approximately 80-times in distilled water and 50-times in pH 6.8 0.2 M phosphate buffer. The compressibility of SPH microparticles increased significantly as the microparticle size increased. The FDTs made of SPH microparticles in the range of 75-106 microm showed the fastest disintegration time and higher tensile strength. SPH microparticle, tableting pressure and ketoprofen had significant effects on disintegration time and tensile strength of ketoprofen FDTs. The FDTs that were prepared with 2.5% w/w SPH microparticles of 75-106 microm at 63 MPa pressure possessed a tensile strength of 84.4 +/- 4.1 N cm(-2) and disintegrated in 15.0 +/- 2.0 s. It was concluded that the poly(acrylic acid) SPH microparticles could serve as a good super-disintegrant decreasing the disintegration time of FDTs.

Acrylic Resins↗
PubMed1983

Acrylic stabilization of the cervical spine for neoplastic disease: evolution of a technique for vertebral body replacement.

The resection of collapsed cervical vertebral bodies affected by malignant lytic lesions often requires innovative methods for stabilization. Over the years, immediate stabilization of the cervical spine has been achieved with acrylic bridges, preformed metallic placement bodies, fibular strut grafts, and other aids. Because acrylic bonds poorly to adjacent bony structures, techniques to assure the adequate fixation of an acrylic bridge between resected vertebral bodies are needed. The possible progression of disease in adjacent bone prompts us to maximize the amount of internal fixation with rods or pins to assure stability. Lasting stability has become more important as the longevity of cancer patients has been increased by multimodality therapy. We report our technique for treating cancer patients with acrylic and pin fixation of the cervical spine after vertebral body excision by the anterior route. Certain modifications of the technique may have advantages over previously reported procedures. Our series of six cases demonstrates the evolution of a technique that allows relatively rapid and easy decompression of the cervical spinal cord and provides immediate stability of the cervical spine. Our indications and contraindications for this procedure are also discussed.

Acrylates↗