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Results 151 - 200 of 1417
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Hunter Lindsay - - 2009
OBJECTIVE: The aim of this study was to assess the erosive potential of a range of commercially available baby drinks in the laboratory. METHODS: The erosive potential of each product was assessed by measuring its initial pH, neutralizable acidity, and ability to erode primary and permanent enamel. These parameters were ...
Carson Laura - - 2009
Acid functionalized single walled carbon nanotubes were covalently grafted to chitosan by first reacting the oxidized carbon nanotubes with thionyl chloride to form acyl-chlorinated carbon nanotubes which are subsequently dispersed in chitosan and covalently grated to form composite material, CNT-chitosan, 1, which was washed several times to remove un-reacted materials. ...
Takagaki Tomohiro - - 2009
The purposes of this study were twofold, namely to evaluate: (1) the effect of hybridization on microtensile bond strength (microTBS) to dentin, and (2) the ultrastructure of the dentin-adhesive interface with 4-META/MMA-TBB resin after acid-base challenge. Dentin surfaces, which received no treatment (NT), 65% phosphoric acid (PA), or 10% citric ...
Wang Tie wei - - 2009
The aim of this study was to generate a new type of nanoparticles made of quaternized chitosan (QCS) and poly (aspartic acid) and to evaluate their potential for the association and delivery of protein drugs. QCS and poly (aspartic acid) were processed to nanoparticles via the ionotropic gelation technique. The ...
Wang X Y - - 2009
This study evaluated the effects of environmental calcium and phosphate on wear resistance, strength, and surface morphology of highly viscous glass-ionomers (HVGICs) (Fuji IX Fast [FN] and KetacMolar [KM]) when exposed to acidic conditions. Fabricated specimens were randomly divided into five groups and kept in acidic solutions (pH 3) with ...
Ge Yuqing - - 2009
Iron oxide nanoparticles modified with meso-2,3-dimercaptosuccinic acid (DMSA), were encapsulated with a natural polymer with abundant primary amino groups, chitosan (CS), to improve their biocompatibility. Characterization was performed using Fourier transform infrared spectroscopy, thermogravimetirc analysis, transmission electron microscope analyses, vibrating sample magnetometer, zeta potential analyzer. It was found that highly ...
Javakhishvili Irakli - - 2009
Amphiphilic poly(epsilon-caprolactone)-b-poly(acrylic acid) (HS-PCL-b-PAA) with a thiol functionality in the PCL terminal has been prepared in a novel synthetic cascade. Initially, living anionic ring-opening polymerization (ROP) of epsilon-caprolactone (epsilon-CL) employing the difunctional initiator, 2-hydroxyethyl 2-bromoisobutyrate, followed by esterification with 2,4-dinitrophenyl- or 4-monomethoxytrityl-protected mercaptoacetic acids (Prot-), provided well-defined PCL macroinitiators capped ...
Hjortsjö C - - 2009
Acidic fluoride solutions may reduce dental erosion. The aim of this study was to compare the effect of different acidic fluoride solutions on enamel dissolution using an established in vivo model. When possible 4 anterior teeth (255 teeth in a total of 67 subjects) were isolated and exposed to 0.01 ...
Miyabe Toshitaka - - 2009
To develop a novel polymer-based asymmetric organocatalyst, a series of helical poly(phenyl isocyanide)s with functional pendant groups were prepared by modifying the side groups of the optically active helical poly(4-carboxyphenyl isocyanide) with a macromolecular helicity memory. Helical polyisocyanides partially modified with achiral amines, such as piperazine, maintained their chiral memory ...
Meireles Sonia Saeger - - 2009
AIM: The aim of this study was to evaluate and compare the surface roughness and enamel loss produced by two microabrasion techniques. METHODS AND MATERIALS: Bovine teeth were selected and an area was delimited for microabrasion techniques. Surface roughness was determined before and after treatment using a digital profilometer. Specimens ...
Costescu Ruxandra M - - 2009
The effect of illumination on the hydrofluoric acid etching of AlAs sacrificial layers with systematically varied thicknesses in order to release and roll up InGaAs/GaAs bilayers was studied. For thicknesses of AlAs below 10 nm, there were two etching regimes for the area under illumination: one at low illumination intensities, ...
Chen Quanyuan - - 2009
Portland cement (PC) and blended cements containing pulverized fuel ash (PFA) or granulated blast-furnace slag (GGBS) were used to solidify/stabilize an electroplating sludge in this work. The acid neutralization capacity (ANC) of the hydrated pastes increased in the order of PC > PC/GGBS > PC/PFA. The GGBS or PFA replacement ...
Zhang Shengzu - - 2008
The polymerizable gelator N-octadecyl maleamic acid (ODMA) can self-assemble in selected polymerizable organic solvents, such as 2-hydroxyethyl methacrylate (HEMA) and methylacrylic acid (MAA) to form thermally stable polymerizable organogels. A mixture consisting of HEMA and MAA as the monomer and functional monomer, PEG dimethacrylates (PEG200DMA) as the crosslinker, BOC-L-phenylalanine (BPA) ...
Bolan M M Department of Stomatology, Federal University of Santa Catarina, Brazil. - - 2008
The higher incidence of dental erosion in children and teenagers possibly reflects a high intake of acidic food and beverages as well as a more frequent diagnosis on this condition. The aim of this study was to evaluate the erosive potential of acidic filling of chewing gum in primary and ...
Eckhaus Allan A AA Institute of Biomaterials and Biomedical Engineering and the Department of Surgery, University of Toronto, Sunnybrook Health Science Center, and Rimon Therapeutics Ltd., Toronto, Ontario, - - 2008
Inadequate blood supply can limit tissue graft size and thickness. As a result, there is considerable interest in vascularization strategies that might extend these limits. Beads of a copolymer of methacrylic acid and methyl methacrylate were used to enhance rat composite myocutaneous skin graft vascularization and to assess the effect ...
Reinecke Frank - - 2009
The Gram-negative, facultative chemolithoautotrophic bacterium Ralstonia eutropha has been intensively investigated for almost 50 years. Today it is the best studied 'Knallgas' bacterium and producer of poly(3-hydroxybutyric acid). This polyester provides the basis for renewable resource-based biodegradable plastic materials and has attracted much biotechnological interest. The polymer is accumulated in ...
Hsu Chih-Wei - - 2009
Two classes of phosphonic acid-bearing organic molecules, 2-oligothiophene phosphonic acid and omega-(2-thienyl)alkyl phosphonic acid were adopted as interface modifiers (IMs) of the TiO(2) surface, to increase its compatibility with poly(3-hexylthiophene) (P3HT). The self-assembled monolayers of these molecules on titania surface were characterized by making contact angle measurements and X-ray photoelectron ...
Gokce Kagan - - 2008
PURPOSE: To evaluate acid-etching effects prior to the application of self-etching primer and the effect of different primer application techniques on dentin shear bond strength (SBS). MATERIALS AND METHODS: Forty human third molar cervical regions were used in this study. The teeth were randomly divided into four groups (n=10) of ...
Devanna Raghu - - 2008
The present study was undertaken to investigate the effect on enamel surface, penetration depth, and bond strength produced by 37% phosphoric acid and 20% sulfated polyacrylic acid as etching agents for direct bonding. Eighty teeth were used to study the efficacy of the etching agents on the enamel surface, penetration ...
Liu Hanmao - - 2008
A new method was employed to solid-phase extract ursolic acid from Ilex kudingcha C. J. Tseng using molecularly imprinted microspheres (MIMs) as the sorbent. Using a surface molecular imprinting technique, MIMs for ursolic acid were prepared with bonded beta-CD and acrylamide in combination based on functionalized poly(glycidyl methacrylate) microspheres (F-PGMA). ...
Ahmed Aya Abdulla Rashid - - 2008
PURPOSE: To determine the extent to which artificial carious dentin can be removed by agents that do not seem to attack sound dentin such as pepsin, trypsin, collagenase and NaOCl, and to evaluate the effect of the enzyme pepsin and a new enzymatic solution SFC-V (pepsin in mild acidic buffer) ...
He Bin - - 2008
Amorphous poly(DL-lactide-co-RS-beta-malic acid) (PDLLMAc) was synthesized by hydrogenolysis of poly(DL-lactide-co-RS-beta-malolactonate) (PDLLMA), which was obtained from the ring-opening polymerization of DL-lactide (DLLA) and RS-beta-benzyl malolactonate (MA) using stannous octoate as the catalyst. The amount of malolactonate (MA) in the feeding dose was varied from 0 to 8.0 mol %. The copolymers ...
Featherstone J D B - - 2008
Abstract Dental caries is a transmissible bacterial disease process caused by acids from bacterial metabolism diffusing into enamel and dentine and dissolving the mineral. The bacteria responsible produce organic acids as a by-product of their metabolism of fermentable carbohydrates. The caries process is a continuum resulting from many cycles of ...
Li Jingguo - - 2008
Synthesis of novel zwitterionic block copolypeptides, poly(N-isopropylacrylamide)-block-poly(L-glutamic acid-co-L-lysine) [PNiPAM(n)(PLG(x)-co-PLLys(y))m , where n is the number-average degree of polymerization (DP(n)) of PNiPAM block, x and y are the mole fraction of glutamic acid and lysine residues, respectively, and m is the total DP(n) of the peptide block], and their stimuli-responsiveness to ...
Knorr Veronika - - 2008
PURPOSE: Dynamic PEG-polycation copolymers that release PEG and degrade into small fragments after cell entry might present efficient and biocompatible gene carriers. METHODS: PEG-OEI-MK was synthesized by copolymerization of 5 kDa polyethyleneglycol (PEG) and 800 Da oligoethylenimines through acid-degradable acetone-bis-(N-maleimidoethyl)ketal linkers (MK). To evaluate any benefit of the reversible over ...
Celik Sevim U - - 2008
The synthesis, thermal and proton conducting properties of copolymers based on vinylphosphonic acid (VPA) and 1-vinyl-1,2,4-triazole (VTri) were investigated. The copolymers were synthesized by free-radical copolymerization of the corresponding monomers at several monomer feed ratios to obtain poly(VPA-co-VTri) copolymer electrolytes. The final structures of the copolymers were confirmed by spectroscopic ...
Sauro S - - 2008
OBJECTIVE: The enamel erosion induced by acidic soft drinks is an increasingly important problem. The aim of this study was to investigate the effect of soft drinks on enamel erosion and the protection offered by representative modern toothpastes using a new 'in situ scanning electron microscopy (SEM)-replica technique'. METHODS: Six ...
Wiegand Annette - - 2008
OBJECTIVE: To investigate and compare the protective impact of the in situ formed salivary pellicle on enamel and dentine erosion caused by different acids at pH 2.6. METHODS: Bovine enamel and dentine samples were exposed for 120 min in the oral cavity of 10 healthy volunteers. Subsequently, enamel and dentine ...
Dayem Raad Niama - - 2010
The objective of this study was to assess the penetration depth of dental adhesive systems through acid-etched dentin, deproteinized by neodymium:yttrium-aluminum-garnet (Nd:YAG) laser or 10% sodium hypochlorite (NaOCl) solution, using fluorescent light microscopy. Sixty extracted human upper premolars were selected to be given standardized buccal and lingual class V cavities. ...
Crovetto Luis - - 2008
The 2,5-dioxopyrrolidin-1-yl-4-(3-hydroxy-6-oxo-6H-xanthen-9-yl)-3-methylbenzoate has been synthesized as an amine-reactive derivative able to yield stable covalently labeled biopolymers. The new derivative has been used to label polyribocytidilic acid (5'), poly(C), amine residues. TG-II-poly(C) exhibits monoexponential decay at the physiological pH range. In addition, both steady-state fluorescence intensity and fluorescence decay are also ...
Wargacki Stephen P - - 2008
The recovery and identification of latent fingerprints from a crime scene are crucial to many investigations. The cyanoacrylate (superglue) fuming method (CFM), which develops fingerprints by growing a polymer coating over the print residue, is a powerful method but encounters severe limitations when prints are aged or exposed to harsh ...
Leite F L - - 2008
The study of intermolecular interactions at interfaces is essential for a number of applications, in addition to the understanding of mechanisms involved in sensing and biosensing with liquid samples. There are, however, only a few methods to probe such interfacial phenomena, one of which is the atomic force spectroscopy (AFS) ...
Rao Jingyi - - 2008
Well-defined AB2 Y-shaped miktoarm star polypeptide copolymer, PZLL-b-(PBLG)2, was synthesized via a combination of ring-opening polymerization (ROP) of alpha-amino acid N-carboxyanhydride (NCA) and click chemistry, where PZLL is poly(epsilon-benzyloxycarbonyl-L-lysine) and PBLG is poly(gamma-benzyl-L-glutamate). First, two types of primary-amine-containing initiators, N-aminoethyl 3,5-bis(propargyloxyl)-benzamide and 3-azidopropylamine, were synthesized and employed for the ROP ...
Moshaverinia Alireza - - 2009
In this study, a methacryloyl derivative of l-proline was synthesized, characterized and incorporated into a conventional glass ionomer cement (GIC) with a polyacid composition. Subsequently, the effects of incorporation of synthesized N-methacryloyl-proline and terpolymer on the GIC's mechanical and working properties were studied. 1-Methacryloylpyrrolidone-2-carboxylic acid was synthesized and used in ...
Griffin Rebecca C - - 2008
Aspartic acid racemization has been found to be an accurate measure of age at death for recent forensic material. This paper examines the practicality of using acid etching of the tooth surface to extract amino acids from the enamel for racemization analysis. By serial etching of the tooth and contamination ...
Watanabe Takayuki - - 2008
This study investigated the effect of prior phosphoric acid etching on the enamel bond strength of five single-step self-etch adhesive systems: Absolute, Clearfil tri-S Bond, Fluoro Bond Shake One, G-Bond and One-Up Bond F Plus. Bovine mandibular incisors were mounted in self-curing resin, and the facial surfaces were wet ground ...
Suge Toshiyuki - - 2008
The aims of this study were to evaluate the effects of CPP method on the crystallinity of apatite powder and on the acid resistance of bovine enamel. Crystallinity degrees of apatite powder before and after CPP treatment were measured by powder X-ray diffraction analysis. Polished bovine enamel specimens treated with ...
Tomiyama Kiyoshi - - 2008
The effect of fluoride-containing orthodontic resin bonding systems on acid resistance of adjacent enamel was evaluated using transversal microradiography. Four fluoride-containing orthodontic resin bonding systems: BeautyOrtho Bond (BO), BeautyOrtho Bond+Salivatect (BOS), Kurasper F (KP), Transbond XT (TB) and a resin-modified glass-ionomer (Fuji Ortho LC (FO)) were used. Superbond Orthomite (SB) ...
Hara Yusuke - - 2008
Here we report the biomimetic polymer that causes self-oscillation driven by the addition of biorelated organic acid. We constructed the built-in system where all of the substrates of the BZ reaction other than biorelated organic substrates were incorporated into the polymer chain. The quarternary copolymer, which includes both of the ...
Kleinman Jack G - - 2008
Acidic macromolecules inhibit calcium oxalate nucleation, growth, aggregation and attachment to cells in vitro. To test for such an effect in vivo we used osmotic minipumps to continuously infuse several doses of the 5.1 kDa poly(acrylic acid) (pAA(5.1)) into rats fed a diet which causes renal calcium oxalate crystal deposition. ...
Salles A G - - 2008
The search for an ideal filler for soft tissue augmentation still continues. Because aging changes are continuous, temporary fillers should be preferred against permanent ones. Since 1999, the poly-L-lactic acid filler (PLA) has been marketed in Europe as Newfill. As a synthetic biocompatible polymer, PLA originally was used in suture ...
Karatzas Anastasis - - 2008
By combining two living polymerizations, anionic and ring opening (ROP), the following novel multiblock multicomponent linear and miktoarm star (micro-star) polymer/polypeptide hybrids (macromolecular chimeras) were synthesized: Linear, PBLL-b-PBLG-b-PS-b-PBLG-b-PBLL; 3micro-stars, (PS)2(PBLG or PBLL), (PS)(PI)(PBLG or PBLL); 4micro-stars, (PS)2[P(alpha-MeS)](PBLG or PBLL), (PS)2(PBLG or PBLL)2 [PS, polystyrene; PI, polyisoprene; P(alpha-MeS), poly(alpha-methylstyrene); PBLG, poly(gamma-benzyl-L-glutamate); ...
Buchko Garry W GW Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, - - 2008
Amelogenin is the predominant matrix protein in developing dental enamel. Making extensive use of residue specific 15N-labeled amino acids samples, the majority of the main and side chain resonances for murine amelogenin were assigned in 2% aqueous acetic acid at pH 3.0.
Chen Wen-Cheng - - 2008
Bone filler has been used over the years in dental and biomedical applications. The present work is to characterize a non-dispersive, fast setting, modulus adjustable, high bioresorbable composite bone cement derived from calcium phosphate-based cement combined with polymer and binding agents. This cement, we hope, will not swell in simulated ...
Qi Mingbo - - 2008
The local delivery and controllable release profiles make electrospun ultrafine fibers as potential implantable drug carriers and functional coatings of medical devices. There are few attempts to form acid-labile electrospun fibers, whose release behaviors respond to the local environment and fiber characteristics. In the current study a novel strategy was ...
Patnukao Phussadee - - 2008
The powdered activated carbon prepared by phosphoric acid activation was significantly affected by the carbonization temperature and the weight ratio between raw material and phosphoric acid. With an activation time of 1h and an impregnation ratio of 1:1, the activated carbons with better adsorption capacity were obtained at 500 degrees ...
Iwaya Yukari - - 2008
The purpose of this study was to evaluate the effects of acid-etched titanium on the biological responses of osteoblast-like MC3T3-E1 cells. Four types of treatments (polishing, sandblasting, concentrated H2SO4 etching, and concentrated H2SO4 etching with vacuum firing) were carried out on the surfaces of commercially pure titanium (cpTi) disks. MC3T3-E1 ...
Miles Peter G - - 2008
AIM: To determine if microetching the mandibular premolars and first molars prior to acid-etching reduced bracket failures during the first six months of orthodontic treatment. METHODS: Sixty four patients with 384 mandibular first molar and premolar brackets were used in a split-mouth study design. In each patient the teeth on ...
Ehlen Leslie A LA College of Dentistry, University of Iowa, - - 2008
Acidic beverages are thought to increase the potential for dental erosion. We report pH and titratable acidities (ie, quantity of base required to bring a solution to neutral pH) of beverages popular in the United States and lesion depths in enamel and root surfaces after beverage exposure, and we describe ...
Hunter Margaret L - - 2008
BACKGROUND: Only one previous study has investigated the effect which dilution has on the erosive potential of dilutable fruit drinks. Based solely on measurement of neutralizable acidity, the authors concluded that the erosive potential of diluting juices may be reduced substantially by the addition of water. This has not been ...
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