Dall'Oca C, Maluta T, Cavani F, Morbioli G P, Bernardi P, Sbarbati A, Degl'Innocenti D, Magnan B
University of Verona.
Eur J Histochem. 2014 Jun 23;58(2):2255. doi: 10.4081/ejh.2014.2255.
Composite cements have been shown to be biocompatible, bioactive, with good mechanical properties and capability to bind to the bone. Despite these interesting characteristic, in vivo studies on animal models are still incomplete and ultrastructural data are lacking. The acquisition of new ultrastructural data is hampered by uncertainties in the methods of preparation of histological samples due to the use of resins that melt methacrylate present in bone cement composition. A new porous acrylic cement composed of polymethylmetacrylate (PMMA) and β-tricalciumphosphate (β-TCP) was developed and tested on an animal model. The cement was implanted in femurs of 8 New Zealand White rabbits, which were observed for 8 weeks before their sacrifice. Histological samples were prepared with an infiltration process of LR white resin and then the specimens were studied by X-rays, histology and scanning electron microscopy (SEM). As a control, an acrylic standard cement, commonly used in clinical procedures, was chosen. Radiographic ultrastructural and histological exams have allowed finding an excellent biocompatibility of the new porous cement. The high degree of osteointegration was demonstrated by growth of neo-created bone tissue inside the cement sample. Local or systemic toxicity signs were not detected. The present work shows that the proposed procedure for the evaluation of biocompatibility, based on the use of LR white resin allows to make a thorough and objective assessment of the biocompatibility of porous and non-porous bone cements.
复合骨水泥已被证明具有生物相容性、生物活性，具备良好的机械性能以及与骨结合的能力。尽管有这些有趣的特性，但在动物模型上进行的体内研究仍不完整，且缺乏超微结构数据。由于骨水泥成分中存在的甲基丙烯酸酯会在制备组织学样本时使用的树脂中熔化，这导致组织学样本制备方法存在不确定性，从而阻碍了新超微结构数据的获取。一种由聚甲基丙烯酸甲酯（PMMA）和β - 磷酸三钙（β - TCP）组成的新型多孔丙烯酸骨水泥被研发出来，并在动物模型上进行了测试。将该骨水泥植入8只新西兰白兔的股骨中，在处死前观察8周。采用LR白色树脂浸润法制备组织学样本，然后通过X射线、组织学和扫描电子显微镜（SEM）对样本进行研究。作为对照，选用了临床手术中常用的丙烯酸标准骨水泥。放射学、超微结构和组织学检查表明，新型多孔骨水泥具有优异的生物相容性。骨水泥样本内部新生骨组织的生长证明了高度的骨整合。未检测到局部或全身毒性迹象。目前的研究表明，基于使用LR白色树脂的生物相容性评估方法能够对多孔和非多孔骨水泥的生物相容性进行全面、客观的评估。
