Department of Prosthodontics, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil.
Int J Oral Maxillofac Implants. 2013 Jul-Aug;28(4):1037-47. doi: 10.11607/jomi.3091.
The objectives of this study were to evaluate the galvanic corrosion behavior between titanium and nickel-chromium (Ni-Cr) alloy, to investigate the effect of diamondlike carbon (DLC) coating over titanium on galvanic corrosion behavior between titanium and Ni-Cr alloy, and to evaluate the effect of DLC coating over titanium abutments on the fit and integrity of prosthetic assemblies by scanning electron microcopy (SEM).
Five Ni-Cr and 10 titanium disks with a diameter of 5 mm and thickness of 3 mm were prepared. DLC coating was applied to five titanium disks. Electrode samples were prepared, and open circuit potential measurements, galvanic current measurements over platinum electrodes, and potentiodynamic polarization tests were carried out. For the SEM evaluation, 20 Ni-Cr alloy and 10 gold alloy superstructures were cast and prepared over 30 abutments. DLC coating was applied to 10 of the abutments. Following the fixation of prosthetic assemblies, the samples were embedded in acrylic resin and cross sectioned longitudinally. Internal fit evaluations were carried out through examination of the SEM images.
Titanium showed more noble and electrochemically stable properties than Ni-Cr alloy. DLC coating over the cathode electrode served as an insulating film layer over the surface and prevented galvanic coupling. Results of the SEM evaluations indicated that the DLC-coated and titanium abutments showed no statistically significant difference in fit. Hence, no adverse effects on the adaptation of prosthetic components were found with the application of DLC coating over abutment surfaces.
DLC coating might serve as a galvanic corrosion barrier between titanium abutments and Ni-Cr superstructures.
本研究旨在评估钛与镍铬（Ni-Cr）合金之间的电偶腐蚀行为，研究钛表面类金刚石碳（DLC）涂层对钛与 Ni-Cr 合金之间电偶腐蚀行为的影响，并通过扫描电子显微镜（SEM）评估钛基台表面 DLC 涂层对修复体组件适配性和完整性的影响。
制备了 5 个 Ni-Cr 合金和 10 个直径为 5mm、厚度为 3mm 的钛合金圆盘。对其中 5 个钛合金圆盘进行 DLC 涂层处理。制备电极样品，进行开路电位测量、铂电极上的电偶电流测量和动电位极化测试。为了进行 SEM 评估，铸造并制备了 20 个 Ni-Cr 合金和 10 个金合金上部结构，共 30 个基台。对其中 10 个基台进行 DLC 涂层处理。在固定修复体组件后，将样品嵌入丙烯酸树脂中并进行纵向切片。通过 SEM 图像检查进行内部适配性评估。
钛的电化学稳定性优于 Ni-Cr 合金，表现出更正的电极电位。阴极电极表面的 DLC 涂层作为绝缘膜层，防止电偶耦合。SEM 评估结果表明，DLC 涂层和钛基台在适配性方面没有统计学上的显著差异。因此，在基台表面应用 DLC 涂层不会对修复体组件的适配性产生不利影响。
DLC 涂层可能作为钛基台和 Ni-Cr 上部结构之间的电偶腐蚀屏障。
