Department of Chemical and Biochemical Engineering, Faculty of Engineering, University of Western Ontario, London, Ontario, Canada N6A 5B9.
J Biomater Appl. 2011 Feb;25(6):515-37. doi: 10.1177/0885328209356944. Epub 2010 Mar 5.
X-ray contrast medium (BaSO(4) or ZrO(2)) used in commercially available PMMA bone cements imparts a detrimental effect on mechanical properties, particularly on flexural strength and fracture toughness. These lower properties facilitate the chance of implant loosening resulting from cement mantle failure. The present study was performed to examine the mechanical properties of a commercially available cement (CMW1) by introducing novel nanostructured titania fibers (n-TiO(2) fibers) into the cement matrix, with the fibers acting as a reinforcing phase. The hydrophilic nature of the n-TiO(2) fibers was modified by using a bifunctional monomer, methacrylic acid. The n-TiO(2) fiber content of the cement was varied from 0 to 2 wt%. Along with the mechanical properties (fracture toughness (K (IC)), flexural strength (FS), and flexural modulus (FM)) of the reinforced cements the following properties were investigated: complex viscosity-versus-time, maximum polymerization temperature (T (max)), dough time (t (dough)), setting time (t (set)), radiopacity, and in vitro biocompatibility. On the basis of the determined mechanical properties, the optimized composition was found at 1 wt% n-TiO(2) fibers, which provided a significant increase in K (IC) (63%), FS (20%), and FM (22%), while retaining the handling properties and in vitro biocompatibility compared to that exhibited by the control cement (CMW1). Moreover, compared to the control cement, there was no significant change in the radiopacity of any of the reinforced cements at p = 0.05. This study demonstrated a novel pathway to augment the mechanical properties of PMMA-based cement by providing an enhanced interfacial interaction and strong adhesion between the functionalized n-TiO( 2) fibers and PMMA matrix, which enhanced the effective load transfer within the cement.
X 射线造影剂(BaSO4 或 ZrO2)用于市售 PMMA 骨水泥会对机械性能产生不利影响,特别是对弯曲强度和断裂韧性。这些较低的性能增加了由于水泥覆盖层失效导致植入物松动的机会。本研究通过在水泥基质中引入新型纳米结构二氧化钛纤维(n-TiO2 纤维)来研究一种市售水泥(CMW1)的机械性能,纤维作为增强相。n-TiO2 纤维的亲水性通过使用双官能单体甲基丙烯酸进行改性。水泥中 n-TiO2 纤维的含量从 0 变化到 2wt%。除了增强水泥的机械性能(断裂韧性(KIC)、弯曲强度(FS)和弯曲模量(FM))之外,还研究了以下性能:复合粘度-时间、最大聚合温度(Tmax)、面团时间(tdough)、凝固时间(tset)、射线照相密度和体外生物相容性。根据确定的机械性能,在 1wt%n-TiO2 纤维的优化组成下,发现断裂韧性(63%)、FS(20%)和 FM(22%)显著增加,同时保持了与对照水泥(CMW1)相比的处理性能和体外生物相容性。此外,与对照水泥相比,任何增强水泥的射线照相密度在 p=0.05 时均无显著变化。本研究通过提供增强的界面相互作用和功能化 n-TiO2 纤维与 PMMA 基质之间的强粘附性,为增强 PMMA 基水泥的机械性能提供了一种新途径,从而增强了水泥内的有效载荷传递。