抄録
Generally, metal clasps are used as a part of the assembly for removable partial dentures (RPDs); however, the color of metal clasps is unaesthetic. On the other hand, non-metal clasp dentures (NMCDs) made from thermoplastic resin are being used more often as esthetic prostheses, but the use of such NMCDs without a metal framework may seriously affect the remaining tissues because of their low rigidity. Consequently, we developed a laboratory glass fiber-reinforced thermoplastic (GFRTP) having excellent esthetics and strength for RPD applications, and examined its physical and mechanical properties. In the present study, the GFRTP made from E-glass fibers and polypropylene was fabricated through pultrusion and hot press methods. The fiber volume fraction of the GFRTP was confirmed to be 36.1% using an ashing technique. A dynamic micro-indentation test confirmed that the fibers do not affect the surface properties of the GFRTP. The flexural strength and flexural modulus of the GFRTP obtained from a flexural test were 170.5 ± 7.4 MPa and 16.7 ± 0.7 GPa, respectively. As a result, the flexural properties of the GFRTP were higher than those of commercially available NMCD materials made of thermoplastics, though they were lower than those of metallic clasp wires, such as those made with cobalt–chromium alloy and stainless steel. With mechanical properties better than those of conventional NMCDs, this newly developed GFRTP is potentially useful for esthetic RPDs.
