氟对变形链球菌黏附前后纯钛表面腐蚀性能的影响

The effect of fluoride on electrochemical corrosion of the dental pure titanium before and after adhesion of Streptococcus mutans

目的 :比较氟化钠对变形链球菌黏附前、后纯钛电化学腐蚀性能的影响。方法 :应用电化学工作站的电化学阻抗谱法和动电位极化曲线法,对变形链球菌黏附前、后纯钛在0 g/L和1.0 g/L氟化钠人工唾液中的腐蚀行为进行比较。采用SPSS12.2软件包对数据进行统计学分析。结果:变形链球菌黏附前、后,纯钛在0g/L和1.0 g/L氟化钠人工唾液中的等效电路极化电阻R_(ct)、腐蚀电位E_(corr)、点蚀击穿电位E_b以及代表合金表面的"伪钝化"的△E(E_(corr)与E_b之差)均存在显著差异(P<0.05)。结论:变形链球菌黏附后,纯钛的耐腐蚀性能降低,氟化钠也使纯钛的耐腐蚀性能降低。

PURPOSE： To investigate the effect of fluoride on electrochemical corrosion of the dental pure titanium before and after adhesion of Streptococcus mutans. METHODS： The dental pure titanium specimens were tested by electrochemical measurement system including electrochemical impedance spectroscopy（EIS） and potentiodynamic polarization curve（PD） methods in artificial saliva with 0 g/L and 1.0 g/L sodium fluoride before and after dipped into culture medium with Streptococcus mutans for 24 h. The corrosion parameters, including the polarization resistance（Rct）,corrosion potential（Ecorr）, pitting breakdown potential（Eb）, and the difference between Ecorrand Ebrepresenting the＂pseudo-passivation＂（△E） obtained from the electrochemical tests were used to evaluate the corrosion resistance of dental pure titanium. The data were statistically analyzed by 2 ×2 factorial statistical analysis to examine the effect of sodium fluoride and adhesion of Streptococcus mutans using SPSS 12.0 software package. RESULTS： The results showed that the corrosion parameters including Rct, Ecorr, Eb, and △E of pure titanium had significant difference between before and after adhesion of Streptococcus mutans in the same solution（P〈0.05）, and in artificial saliva with 0 g/L and 1.0 g/L sodium fluoride（P 0.05）. CONCLUSIONS： The dental pure titanium was prone to corrosion in artificial saliva with sodium fluoride. The corrosion resistance of pure titanium decreased distinctly after immersed in culture medium with Streptococcus mutans.