Department of Dental Materials and Prosthodontics, Univ Estadual Paulista, Araçatuba Dental School, Jose Bonifacio, 1193, Araçatuba, São Paulo, 16015-050, Brazil.
J Dent Res. 2011 May;90(5):613-8. doi: 10.1177/0022034510396880. Epub 2011 Feb 18.
Lipopolysaccharide (LPS) may induce peri-implantitis and implant failure. However, the role of LPS in titanium (Ti) electrochemical behavior remains unknown. We hypothesized that LPS in saliva with different pHs affects Ti corrosion properties. Thirty-six Ti discs (15 mm × 3 mm) were divided into 12 groups according to saliva pH (3, 6.5, and 9) and Escherichia coli LPS concentration (0, 0.15, 15, and 150 µg/mL). Electrochemical tests, such as open circuit potential, potentiodynamic, and electrochemical impedance spectroscopy, were conducted in a controlled environment. Data were evaluated by Pearson correlation and regression analysis (α = 0.05). LPS and pH affected Ti corrosive behavior. In general, lower pH and higher LPS concentration accelerated Ti corrosion. In the control group, the increase of pH significantly reduced the corrosion rate and increased the capacitance of the double layer. In LPS groups, the decrease of pH significantly increased the corrosion rate of Ti. LPS negatively influenced Ti corrosion behavior.
C(dl), capacitance of double layer; E(corr), corrosion potential; EIS, electrochemical impedance spectroscopy; I(corr), corrosion current density; I(pass), passivation current density; LPS, lipopolysaccharide; OCP, open circuit potential; R(p), polarization resistance; Ti, titanium.
脂多糖（LPS）可能会引发种植体周围炎和种植体失败。然而，LPS 在钛（Ti）电化学行为中的作用尚不清楚。我们假设唾液中的 LPS 在不同 pH 值下会影响 Ti 的腐蚀特性。将 36 个 Ti 圆盘（15mm×3mm）根据唾液 pH 值（3、6.5 和 9）和大肠杆菌 LPS 浓度（0、0.15、15 和 150μg/mL）分为 12 组。在受控环境中进行了开路电位、动电位和电化学阻抗谱等电化学测试。数据通过 Pearson 相关性和回归分析进行评估（α=0.05）。LPS 和 pH 值影响 Ti 的腐蚀行为。一般来说，较低的 pH 值和较高的 LPS 浓度会加速 Ti 的腐蚀。在对照组中，pH 值的升高显著降低了腐蚀速率并增加了双层电容。在 LPS 组中，pH 值的降低显著增加了 Ti 的腐蚀速率。LPS 对 Ti 的腐蚀行为有负面影响。
C(dl)，双层电容；E(corr)，腐蚀电位；EIS，电化学阻抗谱；I(corr)，腐蚀电流密度；I(pass)，钝化电流密度；LPS，脂多糖；OCP，开路电位；R(p)，极化电阻；Ti，钛。
