Naslov
EPR Registration of Polymerization in Composite Sample

Autori
Meniga, Andrej ; Tarle, Zrinka ; Sanković, Krešimir ; Šutalo, Jozo

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Journal of Dental Research (0022-0345) 76 (1997), Special Issue, Abstr ; No 473 / Herzberg, Mark C. - Orlando (FL) : International Association for Dental, Oral, and Craniofacial Research (IADR), 1997

Skup
75th General Session and Exhibition of IADR

Mjesto i datum
Orlando (FL), Sjedinjene Američke Države, 19.03.1997. - 23.03.1997

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
polymerization; composite resins

Sažetak
The visible light cured resin composite materials contain camphorquinone (0.17-1.03%) in combination with (0.86-1.39%) N, N-dimethylaminoethyl methacrylate as photosensitizer. Through the influence of blue light occurs the initial photopolymerization step in the complicated process of material setting. Visible light induces cross-linking reactions and generation of radicals which initiate a chain process and ensure the propagation of the growing polymer chain. To check accuratley the polymerization dynamics, some experiments using Electron Paramagnetic Resonance Spectrometer VARIAN 109E (X band ) have been made. An EPR spectrum is a graphical representation of the absorption intensety under the resonance condition due to the magnetic field intensity. Composite materials Valux (3M, USA ) and Tetric (Vivadent, Liechtenstein) and their analogous unfilled resins Schotchbond and Heliobond were tested. Experiments were made with dark and light shades polymerized 10, 20 and 60 s under the temperature controlled conditions (37o C). The correlation between free radicals formation and the degree of conversion has been noticed. Signals obtained after 10 and 20 s. The level of EPR-registrated free radical concetration is directly correlated to the degree of conversion. ( This study was supported by the Ministry of Science and Technology of the Republic of Croatia)

Izvorni jezik
Engleski

Znanstvena područja
Fizika

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