Department of Orthopaedics, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
Center for Atomic and Molecular Technologies, Graduate School of Engineering, Osaka University, Suita, Osaka, Japan.
PLoS One. 2018 Mar 14;13(3):e0194303. doi: 10.1371/journal.pone.0194303. eCollection 2018.
In the physiochemical sciences, plasma is used to describe an ionized gas. Previous studies have implicated plasma surface treatment in the enhancement of hydrophilicity of implanted musculoskeletal reconstructive materials. Hydroxyapatite (HA) ceramics, widely used in bone tissue regeneration, have made great advancements to skeletal surgery. In the present study, we investigate the impact of low-pressure plasma on the interconnected porous calcium hydroxyapatite (IP-CHA) both in vitro and in vivo. Our results indicate that dielectric barrier discharge (DBD) plasma, when used with oxygen, can augment the hydrophilicity of non-porous HA surfaces and the osteoconductivity of the IP-CHA disc via increased water penetration of inner porous structures, as demonstrated through microfocus computed tomography (μCT) assay. In vivo implantation of plasma-treated IP-CHA displayed superior bone ingrowth than untreated IP-CHA. Though plasma-treated IP-CHA did not alter osteoblast cell proliferation, it accelerated osteogenic differentiation of seeded marrow mesenchymal stem cells. In vitro X-ray photoelectron spectroscopy (XPS) revealed that this plasma treatment increases levels of oxygen, rather than nitrogen, on the plasma-treated IP-CHA surface. These findings suggest that plasma treatment, an easy and simple processing, can significantly improve the osteoconductive potential of commonly used artificial bones such as IP-CHA. Further optimization of plasma treatment and longer-term follow-up of in vivo application are required toward its clinical application.
在物理化学科学中，等离子体用于描述离子化气体。先前的研究表明，等离子体表面处理可以提高植入的肌肉骨骼重建材料的亲水性。羟基磷灰石（HA）陶瓷广泛应用于骨组织再生，在骨骼手术方面取得了重大进展。在本研究中，我们研究了低压等离子体对互连多孔钙羟基磷灰石（IP-CHA）的体外和体内影响。我们的结果表明，介质阻挡放电（DBD）等离子体与氧气一起使用，可以通过增加内部多孔结构的水渗透来提高非多孔 HA 表面的亲水性和 IP-CHA 盘的骨传导性，这通过微焦点计算机断层扫描（μCT）测定得到证明。体内植入等离子体处理的 IP-CHA 比未处理的 IP-CHA 显示出更好的骨长入。尽管等离子体处理的 IP-CHA 不会改变成骨细胞的增殖，但它加速了骨髓间充质干细胞的成骨分化。体外 X 射线光电子能谱（XPS）显示，这种等离子体处理会增加等离子体处理的 IP-CHA 表面的氧含量，而不是氮含量。这些发现表明，等离子体处理是一种简单易用的处理方法，可以显著提高常用人工骨（如 IP-CHA）的骨传导能力。需要进一步优化等离子体处理并对体内应用进行更长时间的随访，以实现其临床应用。
