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001-es BibID:	BIBFORM044357
Első szerző:	Keczánné Üveges Andrea (vegyész)
Cím:	Reactive Polymer Nanoparticles for Restoration Materials in Dentistry / A. Uveges, K. Bukovinszki, M. Szaloki, C. Hegedus, J. Borbely
Dátum:	2006
ISSN:	0022-0345
Megjegyzések:	Objective: The aim of this study was to examine the influence of modified resin usingreactive polymer nanoparticles on physical properties of filling materials such as flexuralmodulus, flexural stress and polymerization shrinkage of different composites. Methods:Model compounds applied for the resin modification were prepared from styrene (ST) andethyleneglycol dimethacrylate (EDM) by free-radical copolymerization reaction in solution.The azobis(isobutironitrile) (AIBN) initiator was applied and the reactions were carried outat 60oC . The copolymer samples were analyzed with GPC , DLS, TEM and NMR methods.The resin component of C harisma Flow Line composite was used as reference. Theflexural stress and flexural modulus analysis were done on INSTRON 4302 instrument, andthe polymerization shrinkage was analyzed by mercury dilatometer method. Results: Wehave found that molecular weight (Mw) (20-3100 kDa) and the hydrodynamic diameter(18-100 nm) increased with increasing reaction time (30-340 min). The measurement ofthe pendant double bonds showed that the concentration of the reactive groups increased(23, 41, 60 and 91%) with increasing EDM ratio in the feed (ST/EDM 90/10, 70/30, 30/70and 10/90). Both flexural modulus and flexural stress of composite increased withincreasing reactive group concentration of copolymers. The polymerization shrinkage ofmodified composite was less than that of C harisma Flow Line. C onclusions: The reactivecopolymer nanoparticles can be "co-resin" for new modified composites. Support: Thework was supported by RET (Grant of Regional University Knowledge C enter) contractnumber (RET-06/432/2004) and by ElizaNor Polymers LLC , NJ, USA.
Tárgyszavak:	Természettudományok Kémiai tudományok idézhető absztrakt restoration materilas
Megjelenés:	Journal of Dental Research. - 85 (2006), p. 0299. -
További szerzők:	Bukovinszky Katalin (1973-) (egyetemi tanársegéd, fogszakorvos) Szalóki Melinda (1981-) (vegyész) Hegedűs Csaba (1953-) (fogszakorvos) Borbély János (1950-) (vegyész)
Internet cím:	Szerző által megadott URL Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM044372
Első szerző:	Szalóki Melinda (vegyész)
Cím:	Effect of nano-sized prepolymers to resin matrix of dental composite / M. Szaloki, J. Gall, K. Bukovinszki, J. Borbely, C. Hegedus
Dátum:	2011
ISSN:	0022-0345
Megjegyzések:	Objectives: The knowledge on the efficiency of the organic prepolymers in the dental composites is limited. In thisstudy the influence of reactive polymeric nanoparticles (RPNPs) as nano-sized organic prepolymers on themechanical properties of different composite was examined. The aim of this study is to examine how theorganofillers influence the mechanical and rheological properties as volumetric shrinkage, compression strengthsand viscosity of the dental resin matrices. Methods: Organofillers were polymerized in two types of mole ratios(3/7 and 7/3). Two series of nanocomposites were formed by mixing two types of organofillers and Bis-GMA baseddental resin in the range of 5 and 25 w/w%. The nanoparticles were analyzed by TEM, DLS and 1H-NMR methods.The characterization of reinforced resins was performed by compression strength (Instron 4302), volumetricshrinkage (buoyancy method) and rheology (AR 550) methods. Results: The mean hydrodynamic diameter oforganofillers was in the range of 150 and 350 nm. The Mann-Whitney statistical analysis of contraction datashowed that the shrinkage was significantly decreased by increasing the volume of filler compared to the referenceresin. As a result it was found that the compression strength values (223.72?36.10 MPa) for the nanocompositesmodified with reactive polymeric nanoparticles separated significantly from reference unfilled resin (167.59?26.99MPa). C onclusion: The prepolymerized nanoparticles have remarkable effect on the rheological properties,polymerization shrinkage and compression strength. The photopolymerization shrinkage and compressionstrengths were improved significantly by adding prepolymers due to the specific structure of nanoparticles.
Tárgyszavak:	Orvostudományok Klinikai orvostudományok idézhető absztrakt prepolymers
Megjelenés:	Journal of Dental Research. - 90 : B (2011), p. 0023. -
További szerzők:	Gáll József (1972-) (matematikus, közgazdász) Bukovinszky Katalin (1973-) (egyetemi tanársegéd, fogszakorvos) Borbély János (1950-) (vegyész) Hegedűs Csaba (1953-) (fogszakorvos)
Pályázati támogatás:	TÁMOP 4.2.1/B-09/1/KONV-2010-0007 TÁMOP
Internet cím:	Szerző által megadott URL Intézményi repozitóriumban (DEA) tárolt változat
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