Mystkowska Joanna
Department of Materials Science and Biomedical Engineering, Faculty of Mechanical Engineering, Bialystok University of Technology, Bialystok, Poland.
Acta Bioeng Biomech. 2016;18(4):87-96.
Degradation processes of metallic biomaterials in the oral cavity limit the stability and reliability of dental materials. The influence of environment bacteria Desulfotomaculum nigrificans sulfate reducing bacteria on the corrosion processes of Co-Cr-Mo and Ti-6Al-4V alloys was assessed.
After 28 and 56 days of contact of the materials with the bacterial environment, the surfaces of the biomaterials tested were observed by means of confocal scanning laser microscopy (CSLM), and their chemical composition was studied using X-Ray Photoelectron Spectrometry (XPS).
Corrosive changes and the presence of sulfur (with medium atomic concentration of 0.5% for Co-Cr-Mo and 0.3% for Ti-6AL-4V) were observed on the surface of the biomaterials. Image analysis conducted using Aphelion software indicated that corrosion pits took up approx. 2.3% and 1.8% (after 28 days) and 4.2% and 3.1% (after 56 days) of the total test surfaces of cobalt and titanium alloys respectively. The greatest number of corrosion pits had a surface area within the range of 1-50 m2. They constituted from 37% up to 83% of all changes, depending on the type of material.
An evident influence of the SRB on the surfaces of cobalt and titanium alloys was observed. Significant corrosive losses caused by the activity of microorganisms were observed on the metallic surfaces under study. The results of this study have much cognitive and utilitarian significance.
口腔中金属生物材料的降解过程限制了牙科材料的稳定性和可靠性。评估了环境细菌——黑色脱硫肠状菌（一种硫酸盐还原菌）对钴铬钼合金和钛6铝4钒合金腐蚀过程的影响。
材料与细菌环境接触28天和56天后，通过共聚焦扫描激光显微镜（CSLM）观察测试生物材料的表面，并使用X射线光电子能谱（XPS）研究其化学成分。
在生物材料表面观察到腐蚀变化以及硫的存在（钴铬钼合金中硫的原子浓度为0.5%，钛6铝4钒合金中为0.3%）。使用Aphelion软件进行的图像分析表明，腐蚀坑分别占钴合金和钛合金总测试表面的约2.3%和1.8%（28天后）以及4.2%和3.1%（56天后）。最大数量的腐蚀坑表面积在1 - 50μm²范围内。根据材料类型，它们占所有变化的37%至83%。
观察到硫酸盐还原菌对钴合金和钛合金表面有明显影响。在所研究的金属表面观察到微生物活动导致的显著腐蚀损失。本研究结果具有重要的认知和实用意义。
