Figure 1: Mechanical properties for PFC, PFC with 28.2 vol% 3.0 mm chopped quartz fibers, and amalgam with 48 hr set. Regression with variability and values for chopped quartz-fiber lengths of 0.0 mm, 0.5 mm, 1.0 mm, 2.0 mm, and 3.0 mm. (a) Flexural strength, (b) modulus, (c) yield strength, (d) resilience, (e) work of fracture, (f) critical strain energy release, (g) critical stress intensity factor, and (h) strain at peak load. For comparisons: human dentin tensile strength 104 MPa and modulus 13.7 GPa [39] and soaked in water approximately 2.5 MPa⋅m1/2 [40]; human enamel modulus 48 GPa [41] to 94 GPa and    MPa⋅m1/2 [42]; human bone longitudinal, cortical, and tensile strength 70–150 MPa, yield strength 30–70 MPa, and modulus 15–30 GPa [43].