title: Influence of composition and powder/liquid ratio on setting characteristics and mechanical properties of autopolymerized hard direct denture reline resins based on methyl methacrylate and ethylene glycol dimethacrylate.
abstract: We evaluated the influence of composition and powder/liquid (P/L) ratio on the setting characteristics and mechanical properties of autopolymerized hard direct denture reline resins composed of methyl methacrylate (MMA, monomethacrylate) and ethylene glycol dimethacrylate [EGDMA, dimethacrylate (cross-linking agent)], with poly (ethyl methacrylate) used as the powder, and a mixture of MMA and EGDMA containing p-tolyldiethanolamine as the monomer. Setting times were determined using an oscillating rheometer and mechanical properties were based on ISO specifications. Setting time increased exponentially with an increase in the ratio of EGDMA to MMA and decrease in P/L ratio. Materials with a liquid component of approximately 75-85 wt% EGDMA and a higher P/L ratio showed higher ultimate flexural strength and flexural modulus. Our results suggest that setting characteristics are more influenced by the ratio of monomethacrylate and cross-linking agent, whereas mechanical properties are more influenced by P/L ratio.
authors.affiliation: Department of Prosthetic Dentistry, Graduate School of Biomedical Sciences, Nagasaki University.
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Okuyama
authors.forename: Takanobu
authors.initials: T
authors.lastname: Shiraishi
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Yoshida
authors.forename: Tadafumi
authors.initials: T
authors.lastname: Kurogi
authors.forename: Ikuya
authors.initials: I
authors.lastname: Watanabe
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Murata
mesh_terms: D003188:Composite Resins; D003822:Denture Liners; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry*; D020366:Methylmethacrylate / Q000737:chemistry*; D058105:Polymerization
chemical_list: D003188:Composite Resins; D008689:Methacrylates; D020366:Methylmethacrylate; C004919:ethylene dimethacrylate