title: Application of a glass fiber-reinforced composite material to clasps--the effects of immersion and repeated loading.
abstract: The aim of this study was to investigate the effects of water immersion and repeated loading on the mechanical properties of a glass fiber-reinforced composite (FRC) material. Measurements for three-point flexural tests were made at three different temperatures and cross-head speeds, while measurements for fatigue tests were made under three different loads in air or water at 37 degrees C after each cycle. The flexural strength and elastic modulus of the immersed specimens were significantly lower than those of the dry specimens at the same cross-head speed and temperature. On the whole, the values were inferior to those of metal. The deflection increased significantly as the load increased, but there were no significant differences between the values of dry and immersed specimens. With increasing load and number of cycles, the permanent deformation of both specimens increased significantly. The permanent deformation was similar to that of Co-Cr alloy. Based on the results of this study, it is recommended that more effort be devoted to exploring and devising shapes that would render FRC clasp arms with mechanical and physical properties that differ favorably from those of metal.
authors.affiliation: Denture Prosthodontic Restoration, Advanced Dentistry Center, Kagoshima University Medical and Dental Hospital, 8-35-1 Sakuragaoka, Kagoshima, 890-8544, Japan. chie@dentb.hal.kagoshima-u.ac.jp
authors.forename: Chie
authors.initials: C
authors.lastname: Kishita
authors.forename: Tohru
authors.initials: T
authors.lastname: Hamano
authors.forename: Kazunori
authors.initials: K
authors.lastname: Tsuru
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Nishi
authors.forename: Eiichi
authors.initials: E
authors.lastname: Nagaoka
mesh_terms: D000704:Analysis of Variance; D003188:Composite Resins / Q000737:chemistry*; D016734:Dental Clasps; D003799:Dental Stress Analysis; D004548:Elasticity; D005898:Glass; D007101:Immersion; D008422:Materials Testing; D018583:Pliability; D018709:Statistics, Nonparametric
chemical_list: D003188:Composite Resins; C009753:fiberglass