[Fundamental study on photocured resin for crown and bridge]

The purpose of this study is to clarify the superiority of five polyfunctional acrylates to composite filler and comonomer system, and the reasonable concentration of catalyst, Camphor quinone/Dimethylamino-ethylmethacrylate (CQ/DMAEMA), in the photocured resin for crown and bridge. The results are summarized as follows: 1. The influence of acrylate resin matrix of composite fillers was found in the elastic modulus (Em), Knoop hardness (Hk) and the wear resistance (Rw) of the photocured resin. Two photocured resins including Dipentaerythrytol hexaacrylate (DPHA) or DPHA-4(3-acryloxy propyl) tetramethylol methane (DPHA-APTM) composite fillers showed a higher Em, Hk and Rw but slightly lower tensile strength (Ts) and bending strength (Bs) than the one which included Bis-2-methacryloxyethyl 2, 2, 4-trymethyl hexamethylene diurethane (UDMA) or Trimethylolpropane trimethacrylate (TMPTMA) under a wet condition. And these two resins showed as a high water sorption value (Ws) as that of the photocured resin of UDMA. 2. The conversion of polymerization, cured depth and physical properties (Em, Hk and Rw) of the photocured resins were examined. They increased up to 0.5/1.0 or 1.0/1.0 in proportion to the increase of the concentration of the catalysts (CQ/DMAEMA). 3. When DPHA was added into the photocured resins consisted with UDMA monomer and DPHA or DPHA-APTM composite fillers, these resins showed a higher Em, Hk and Rw than the photocured resin with only UDMA as monomer. No significant difference of Ts and Bs between the photocured resins with and without DPHA was observed under a dry condition, but the values of Ts and Bs decreased in proportion to the increase of DPHA monomer under the wet condition. The residual monomer of the photocured resins was less than 1.2 per cent.