Mukaddam Khaled, Astasov-Frauenhoffer Monika, Fasler-Kan Elizaveta, Marot Laurent, Kisiel Marcin, Meyer Ernst, Köser Joachim, Waser Marcus, Bornstein Michael M, Kühl Sebastian
Department of Oral Surgery, University Center for Dental Medicine Basel (UZB), University of Basel, Mattenstrasse 40, 4058 Basel, Switzerland.
Department Research, University Center for Dental Medicine Basel (UZB), University of Basel, Mattenstrasse 40, 4058 Basel, Switzerland.
Materials (Basel). 2021 Dec 13;14(24):7686. doi: 10.3390/ma14247686.
The transgingival part of titanium implants is either machined or polished. Cell-surface interactions as a result of nano-modified surfaces could help gingival fibroblast adhesion and support antibacterial properties by means of the physico-mechanical aspects of the surfaces. The aim of the present study was to determine how a nanocavity titanium surface affects the viability and adhesion of human gingival fibroblasts (HGF-1). Additionally, its properties against were tested.
Two different specimens were evaluated: commercially available machined titanium discs (MD) and nanostructured discs (ND). To obtain ND, machined titanium discs with a diameter of 15 mm were etched with a 1:1 mixture of 98% HSO and 30% HO (piranha etching) for 5 h at room temperature. Surface topography characterization was performed via scanning electron microscopy (SEM) and atomic force microscopy (AFM). Samples were exposed to HGF-1 to assess the effect on cell viability and adhesion, which were compared between the two groups by means of MTT assay, immunofluorescence and flow cytometry. After incubation with , antibacterial properties of MD and ND were determined by conventional culturing, live/dead staining and SEM. Results The present study successfully created a nanostructured surface on commercially available machined titanium discs. The etching process created cavities with a 10-20 nm edge-to-edge diameter. MD and ND show similar adhesion forces equal to about 10-30 nN. The achieved nanostructuration reduced the cell alignment along machining structures and did not negatively affect the proliferation of gingival fibroblasts when compared to MD. No differences in the expression levels of both actin and vinculin proteins, after incubation on MD or ND, were observed. However, the novel ND surface failed to show antibacterial effects against .
Antibacterial effects against cannot be achieved with nanocavities within a range of 10-20 nm and based on the piranha etching procedure. The proliferation of HGF-1 and the expression levels and localization of the structural proteins actin and vinculin were not influenced by the surface nanostructuration. Further studies on the strength of the gingival cell adhesion should be performed in the future.
Since osseointegration is well investigated, mucointegration is an important part of future research and developments. Little is known about how nanostructures on the machined transgingival part of an implant could possibly influence the surrounding tissue. Targeting titanium surfaces with improved antimicrobial properties requires extensive preclinical basic research to gain clinical relevance.
钛种植体的龈下部分可以是机械加工的或经过抛光处理的。纳米改性表面所产生的细胞表面相互作用，可通过表面的物理机械特性，有助于牙龈成纤维细胞的黏附，并具有抗菌性能。本研究的目的是确定纳米腔钛表面如何影响人牙龈成纤维细胞（HGF-1）的活力和黏附。此外，还测试了其针对[具体菌种未给出]的性能。
评估了两种不同的样本：市售的机械加工钛盘（MD）和纳米结构盘（ND）。为了获得ND，将直径为15mm的机械加工钛盘在室温下用98%硫酸和30%过氧化氢的1:1混合物（发烟硫酸蚀刻）蚀刻5小时。通过扫描电子显微镜（SEM）和原子力显微镜（AFM）进行表面形貌表征。将样本暴露于HGF-1以评估对细胞活力和黏附的影响，并通过MTT法、免疫荧光和流式细胞术在两组之间进行比较。在与[具体菌种未给出]孵育后，通过常规培养、活/死染色和SEM测定MD和ND的抗菌性能。结果：本研究成功地在市售的机械加工钛盘上创建了纳米结构表面。蚀刻过程产生了边缘到边缘直径为10 - 20nm的空洞。MD和ND显示出相似的黏附力，约为10 - 30nN。与MD相比，所实现的纳米结构化减少了沿加工结构的细胞排列，并且对牙龈成纤维细胞的增殖没有负面影响。在MD或ND上孵育后，未观察到肌动蛋白和纽蛋白两种蛋白质表达水平的差异。然而，新型ND表面对[具体菌种未给出]未显示出抗菌效果。
基于发烟硫酸蚀刻工艺，在10 - 20nm范围内的纳米腔无法实现对[具体菌种未给出]的抗菌效果。HGF-1的增殖以及结构蛋白肌动蛋白和纽蛋白的表达水平和定位不受表面纳米结构化的影响。未来应进一步研究牙龈细胞黏附的强度。
由于骨结合已得到充分研究，黏膜结合是未来研究和发展的重要组成部分。关于种植体机械加工的龈下部分的纳米结构如何可能影响周围组织，人们知之甚少。针对具有改善抗菌性能的钛表面需要进行广泛的临床前基础研究以获得临床相关性。
