CDP2T and Department of Mechanical Engineering, Setúbal School of Technology, Instituto Politécnico de Setúbal, Campus IPS, Estefanilha, 2914-761, Setúbal, Portugal.
CeFEMA, Instituto Superior Técnico, ULisboa; Av. Rovisco Pais 1, 1049-001, Lisbon, Portugal.
J Biomed Mater Res B Appl Biomater. 2019 Jul;107(5):1393-1399. doi: 10.1002/jbm.b.34231. Epub 2018 Sep 29.
This study aims to understand microorganisms' effect and relevance of aseptic conditions on wear performance of dental materials. Tribocouple zirconia/titanium was submitted to tribological tests in the presence of Streptococcus salivarius biofilm, the most abundant bacteria in the oral cavity. Reciprocating ball-on-plate tests were carried out at 37°C, pH 7, 2 N, and 1 Hz, during 2 h, using Ti6Al4V balls as pins and Y-TZP plates. Simultaneous OCP readings assessed corrosion tendency. Tested lubricants were artificial saliva, artificial saliva plus glucose, and artificial saliva plus glucose and S. salivarius. Wear volume and worn surfaces were analyzed after test. S. salivarius proliferation was enhanced in artificial saliva plus glucose. When a highly populated biofilm was present at the zirconia/titanium interface, titanium wear decreased by ~60% compared to artificial saliva and artificial saliva plus with glucose, respectively, with 0.0060 and 0.0053 mm loss. Wear was not observed in zirconia under any tested condition. Presence of S. salivarius also decreased corrosion activity during wear. Lowest free OCP value reached during sliding was -260 mV in artificial saliva, -246 mV in artificial saliva plus glucose, and -196 mV in artificial saliva plus glucose and bacteria. This decreased to -147 mV when a highly-populated S. salivarius biofilm was present at the interface. Overall, obtained results show that the presence of S. salivarius clearly changes the corrosion-wear performance of the tested dental materials, confirming that it must be recognized, and that asepsis level and conditions during wear test of dental materials must be clearly established and controlled to ensure reproducible results and supported conclusions. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1393-1399, 2019.
本研究旨在了解微生物对口腔环境中最丰富的细菌——唾液链球菌（Streptococcus salivarius）对牙科材料磨损性能的影响和相关性。将氧化锆/钛摩擦副置于唾液链球菌生物膜中进行摩擦学试验，在 37°C、pH7、2N 和 1Hz 条件下，用 Ti6Al4V 球作为销钉，Y-TZP 板作为圆盘，进行往复式球盘摩擦试验。同时进行 OCP 读数以评估腐蚀倾向。试验中使用的润滑剂为人工唾液、人工唾液加葡萄糖和人工唾液加葡萄糖加 S. salivarius。试验后分析磨损体积和磨损表面。人工唾液加葡萄糖中 S. salivarius 增殖增强。当氧化锆/钛界面存在高密度生物膜时，与人工唾液和人工唾液加葡萄糖相比，钛的磨损减少了约 60%，分别损失了 0.0060 和 0.0053mm。在任何测试条件下，氧化锆都没有观察到磨损。S. salivarius 的存在也降低了磨损过程中的腐蚀活性。在人工唾液中，滑动过程中达到的最低自由 OCP 值为-260mV，在人工唾液加葡萄糖中为-246mV，在人工唾液加葡萄糖和细菌中为-196mV。当界面存在高密度 S. salivarius 生物膜时，该值降至-147mV。总的来说，研究结果表明，S. salivarius 的存在明显改变了所测试牙科材料的腐蚀磨损性能，这证实了必须对其进行识别，并且必须明确规定和控制牙科材料磨损试验的无菌水平和条件，以确保可重复的结果和支持的结论。 © 2018 Wiley Periodicals, Inc. J 生物材料研究杂志 B: 应用生物材料 107B: 1393-1399, 2019。
