Abstract
Efficacy of the usage of an experimental fiberβreinforced composite (FRC) on mechanical properties of an indirect composite was investigated by means of threeβpoint bending and Charpy impact tests. Bond strength between the FRC and the indirect composite was also evaluated by tensile testing. The FRC consisted of a matrix resin with 25% silanized milled glass fiber (11βΞΌm diameter, 150βΞΌm length) and 5% colloidal silica. The values of strain of proportional limit, total strain, and fracture energy of the FRC during the bending test (1.2%, 10.4%, and 41.6 Γ 10^β3^ J) were significantly higher than those of the indirect composite (0.1%, 2.5%, and 11.9 Γ 10^β3^ J). The impact strengths of the 1βmm specimens with FRC ranged from 15.2 to 15.9 kJ/m^2^, and were significantly higher than that of the control (3.1 kJ/m^2^). The 2βmm specimens showed significant difference from the control when the FRC thickness was equal or greater than 0.5 mm. The bond strength after the thermocycling was 15.2 MPa, and all of the specimens exhibited cohesive fracture inside the indirect composite. Based upon the results, it was concluded that the FRC tested in this study improved toughness and impact resistance of the indirect composite. The interfacial bonding between the FRC and the indirect composite was strong enough to prevent delamination. Β© 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006