title: Radiation effects of carbon ions and gamma ray on UDMA based dental resin.
abstract: The radiation effects on the mechanical and physical properties of photo-polymerized UDMA resin without filler was investigated by various mechanical tests and spectroscopic measurements. The radiation sources were carbon ion (12C ion) and gamma ray (gamma-ray). With 640 Gy of 12C ion radiation, Vickers hardness increased by about 40%, the degree of abrasion decreased by 30%, and the flexural strength increased by 20%. With the same dose of gamma-ray radiation, only Vickers hardness increased by 19%. The spectra taken by the Fourier Transform Infrared Spectrometer (FT-IR), Raman spectroscopy, and Fluorescence spectrophotometer showed little change in the peak configuration and background intensities. The relative degree of conversion (DC) of carbon double bonds by radiation to the state of non-radiated samples were estimated by FT-IR. Spectroscopic results were indicative for the formation of cross-linking between carbon chains. Cross-linking of carbon molecules induced by radiation might be one of the reasons for the improved mechanical properties of UDMA resin.
authors.affiliation: Division of Dental Materials And Engineering (Department of Oral Health Science), Hokkaido University Graduate School of Dental Medicine, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Haque
authors.forename: S
authors.initials: S
authors.lastname: Takinami
authors.forename: F
authors.initials: F
authors.lastname: Watari
authors.forename: M H
authors.initials: MH
authors.lastname: Khan
authors.forename: M
authors.initials: M
authors.lastname: Nakamura
mesh_terms: D002244:Carbon / Q000737:chemistry; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003764:Dental Materials / Q000737:chemistry / Q000528:radiation effects*; D005720:Gamma Rays; D006244:Hardness; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry / Q000528:radiation effects*; D018583:Pliability; D011140:Polyurethanes / Q000737:chemistry / Q000528:radiation effects*; D013050:Spectrometry, Fluorescence; D017550:Spectroscopy, Fourier Transform Infrared; D013057:Spectrum Analysis; D013059:Spectrum Analysis, Raman; D013223:Statistics as Topic; D013314:Stress, Mechanical; D013499:Surface Properties; D013816:Thermodynamics; D017155:Wettability
chemical_list: D003764:Dental Materials; D008689:Methacrylates; D011140:Polyurethanes; C029824:urethane dimethacrylate luting resin; D002244:Carbon