Doctoral student, Department of Prosthodontics, Faculty of Dentistry, Istanbul University, Istanbul, Turkey; Assistant Professor, Department of Prosthodontics, Faculty of Dentistry, Biruni University, Istanbul, Turkey.
Professor, Department of Prosthodontics, Faculty of Dentistry, Istanbul University, Istanbul, Turkey; Professor, Department of Prosthodontics, Faculty of Dentistry, Istanbul Kent University, Istanbul, Turkey.
J Prosthet Dent. 2022 Sep;128(3):529.e1-529.e10. doi: 10.1016/j.prosdent.2022.06.011. Epub 2022 Aug 5.
How the corrosion properties of cobalt-chromium (Co-Cr) and Ti (Ti-6Al-4V) alloys, frequently used in dental prostheses, are affected by different production methods is unclear.
The purpose of this in vitro study was to compare Co-Cr and Ti-6Al-4V alloys produced by computer-aided design and computer-aided manufacturing (CAD-CAM) milling or laser sintering in terms of corrosion, ion release, and surface hardness.
Co-Cr and Ti-6Al-4V specimens were produced by CAD-CAM milling and direct metal laser sintering/selective laser sintering techniques. Testing included Vickers hardness and then open circuit potential (OCP), Tafel extrapolation, and static immersion to determine the corrosion behavior. The study used an inductively coupled plasma mass spectrometer to measure ion release. The data were analyzed by using the Kruskal-Wallis and Mann-Whitney U tests, with Bonferroni correction (α=.05).
The Ti-6Al-4V laser-sintered group showed the highest Vickers hardness value (P<.008), the lowest OCP value (P<.008), and the lowest corrosion potential (V) value (P<.008). The corrosion current density (I) level of the Co-Cr CAD-CAM milling group was statistically significantly lower than that of the Ti-6Al-4V CAD-CAM milling and the Ti-6Al-4V laser-sintered groups (P<.008). The highest weight change was observed in the Ti-6Al-4V laser-sintered group. The Co, Cr, and Ti ion emissions were higher in specimens produced by laser sintering (P<.05), and no statistically significant difference in terms of Al and V oscillations was found among the groups (P>.05).
Ti-6Al-4V alloys may be a good alternative for patients with Co-Cr allergies, but as per the results of this study, Co-Cr still seems more suitable for clinical use.
钴铬（Co-Cr）和钛（Ti-6Al-4V）合金经常用于牙科假体，其腐蚀性能受不同生产方法的影响尚不清楚。
本体外研究的目的是比较计算机辅助设计和计算机辅助制造（CAD-CAM）铣削或激光烧结生产的 Co-Cr 和 Ti-6Al-4V 合金的腐蚀、离子释放和表面硬度。
通过 CAD-CAM 铣削和直接金属激光烧结/选择性激光烧结技术生产 Co-Cr 和 Ti-6Al-4V 试件。测试包括维氏硬度，然后进行开路电位（OCP）、塔菲尔外推和静态浸泡，以确定腐蚀行为。研究使用电感耦合等离子体质谱仪测量离子释放。使用 Kruskal-Wallis 和 Mann-Whitney U 检验，并用 Bonferroni 校正（α=.05）对数据进行分析。
Ti-6Al-4V 激光烧结组的维氏硬度值最高（P<.008），OCP 值最低（P<.008），腐蚀电位（V）值最低（P<.008）。Co-Cr CAD-CAM 铣削组的腐蚀电流密度（I）水平明显低于 Ti-6Al-4V CAD-CAM 铣削组和 Ti-6Al-4V 激光烧结组（P<.008）。Ti-6Al-4V 激光烧结组的重量变化最大。激光烧结生产的试件中 Co、Cr 和 Ti 离子的排放量较高（P<.05），但各组之间 Al 和 V 波动没有统计学差异（P>.05）。
Ti-6Al-4V 合金可能是对 Co-Cr 过敏患者的良好替代品，但根据本研究结果，Co-Cr 似乎仍然更适合临床使用。
