Norman T L, Kish V, Blaha J D, Gruen T A, Hustosky K
Department of Orthopedics, West Virginia University, Morgantown 26506-9197, USA.
J Biomed Mater Res. 1995 Apr;29(4):495-501. doi: 10.1002/jbm.820290409.
Compressive creep testing of cylindrical specimens machined from two commercial self-polymerizing acrylic bone cements demonstrated measurable creep strains with higher creep strains for the hand-mixed cement specimens compared to vacuum-mixed cement ones. The average creep strains of hand-mixed cement, after 6 h of constant load, ranged from 0.11% at 10.5 MPa to 14.0% at 50 MPa of applied stress. Vacuum mixing reduced the average creep strain to 6.7% after 6 h of applied stress at 50 MPa. There were no significant differences in the creep response between the two types of acrylic cements. The difference in creep resistance of the two cements was reduced after vacuum mixing (P = .013), which also significantly reduced the cement's internal porosity.
对两种商用自聚合丙烯酸骨水泥加工而成的圆柱形试样进行的压缩蠕变测试表明，手工搅拌水泥试样的蠕变应变可测量，且与真空搅拌水泥试样相比，其蠕变应变更高。在持续加载6小时后，手工搅拌水泥的平均蠕变应变在施加应力为10.5 MPa时为0.11%，在50 MPa时为14.0%。在50 MPa的施加应力下，经过6小时的施加应力后，真空搅拌使平均蠕变应变降低至6.7%。两种类型的丙烯酸骨水泥之间的蠕变响应没有显著差异。真空搅拌后，两种水泥的抗蠕变性能差异减小（P = 0.013），这也显著降低了水泥的内部孔隙率。
