Because of its excellent osteoconductivity and bone-replacement capability, self-setting @entity78 cement (CPC) has been used in a number of clinical procedures. For more rapid resorption and concomitant osseointegration, methods were desired to build macropores into CPC; however, this decreased its mechanical properties. The aims of this study, therefore, were to use fibers to strengthen macroporous CPC and to investigate the effects of the pore volume fraction on its mechanical properties. Water-soluble @entity2656 crystals were incorporated into CPC paste; the set CPC was then immersed in water to dissolve @entity2656 , producing macropores. @entity2656 /( @entity2656 + CPC powder) mass fractions of 0, 10, 20, 30, and 40% were used. An aramid fiber volume fraction of 6% was incorporated into the CPC- @entity2656 specimens, which were set in 3 mm x 4 mm x 25 mm molds and then fractured in three-point flexure to measure the strength, work of @entity174 , and modulus. The dissolution of @entity2656 created well-formed macropores, with CPC at 40% @entity2656 having a total porosity of a 70.8% volume fraction. Increasing the @entity2656 content significantly decreased the properties of CPC without fibers (analysis of variance; p < 0.001). The strength (mean +/- standard deviation; n = 6) of CPC at 0% @entity2656 was 15.0 +/- 1.8 MPa; at 40% @entity2656 , it decreased to 1.4 +/- 0.4 MPa. Fiber reinforcement improved the properties, with the strength increasing threefold at 0% @entity2656 , sevenfold at 30% @entity2656 , and nearly fourfold at 40% @entity2656 . The work of @entity174 increased by 2 orders of magnitude, but the modulus was not changed as a result of fiber reinforcement. A scanning electron microscopy examination of specimens indicated @entity42747 and bridging by fibers, matrix multiple cracking, and frictional pullout of fibers as the reinforcement mechanisms. Macroporous CPCs were substantially strengthened and toughened via fiber reinforcement. This may help extend the use of CPCs with macropores for bony ingrowth to the repair of larger defects in stress-bearing locations.

Strong and macroporous XXXX cement: Effects of porosity and fiber reinforcement on mechanical properties.

@entity2656 :: ('MESH:D008353', 'Chemical') :: ['Mannitol', 'mannitol'] @entity78 :: ('MESH:C020243', 'Chemical') :: ['calcium phosphate'] @entity174 :: ('MESH:D050723', 'Disease') :: ['fracture'] @entity42747 :: ('MESH:D003387', 'Disease') :: ['crack deflection']
@entity78 :: (MESH:C020243,Chemical) :: ['calcium phosphate']
