Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, India.
Department of Orthopaedics/Centre for Stem Cell Research, Christian Medical College, Vellore, India; Department of Orthopaedics, Royal Darwin Hospital, Tiwi, Australia.
Nanomedicine. 2020 Oct;29:102232. doi: 10.1016/j.nano.2020.102232. Epub 2020 Jun 17.
Healing or reconstruction of critical-sized bone defects is still challenging in orthopaedic practice. In this study, we developed a new approach to control the degradation and improve the bone regeneration of the AZ31 magnesium substrate, fabricated as mesh cage implants. Subsequently, bilayer nanocomposite coating was carried out using polycaprolactone (PCL) and nano-hydroxyapatite (nHA) by dip-coating and electrospinning. Lastly, the healing capacity of the implants was studied in New Zealand White (NZW) rabbit critical-sized femur bone defects. X-ray analysis showed the coated implant group bridged and healed the critical defects 100% during four weeks of post-implantation. Micro-computed tomography (Micro-CT) study showed higher total bone volume (21.10%), trabecular thickness (0.73), and total porosity (85.71%) with bilayer coated implants than uncoated. Our results showed that nanocomposite coated implants controlled the in vivo degradation and improved bioactivity. Hence, the coated implants can be used as a promising bioresorbable implant for critical segmental bone defect repair applications.
在骨科实践中，治愈或重建临界尺寸的骨缺损仍然具有挑战性。在这项研究中，我们开发了一种新方法来控制 AZ31 镁基体的降解并改善其骨再生能力，该基体被制成网笼植入物。随后，通过浸涂和静电纺丝法在双层纳米复合材料涂层上涂覆聚己内酯（PCL）和纳米羟基磷灰石（nHA）。最后，在新西兰白兔临界尺寸股骨骨缺损模型中研究了植入物的愈合能力。X 射线分析显示，涂层植入物组在植入后 4 周内 100%桥接并愈合了临界缺损。微计算机断层扫描（Micro-CT）研究表明，与未涂层的相比，双层涂层植入物具有更高的总骨体积（21.10%）、骨小梁厚度（0.73）和总孔隙率（85.71%）。我们的结果表明，纳米复合材料涂层植入物控制了体内降解并提高了生物活性。因此，涂层植入物可用作有前途的可生物降解植入物，用于治疗临界节段性骨缺损。
