Cheng, W., H. Yu, X. Lin, X. Han, L. Liu, T. Ding, and P. Ji. [The effect of fluoride on dental alloys in different concentrations of fluoride artificial saliva]. Hua Xi Kou Qiang Yi Xue Za Zhi. 2012 Feb;30(1):18-21. [Article in Chinese]
OBJECTIVE: To study the changes in surface morphology of cobalt-chromium alloy, pure titanium and high-cobalt chromium molybdenum alloy immersed in artificial saliva with different concentrations of fluoride, and to analyze the corrosion resistance of these metals.
METHODS: The three kinds of metal were polished and then were immersed in artificial saliva with different concentrations of fluoride (0%, 0.05%, 0.2%). All specimens were immersed for 3 weeks at (37.0 +/- 1.0) degrees C. Metal surface roughness before and after immersion were measured and analyzed by scanning electron microscope (SEM).
RESULTS: Metal surface roughness was increased with the concentration of fluoride. The surface roughness of the Co-Cr group and Ti group had a statistically significant difference between before and after immersion at the fluoride concentration of 0.05% (P<0.01), and the difference between Co-Cr group and vitallium2000 group, Ti group and vitallium2000 group were statistically significant difference (P<0.01). The differences of three groups before and after immersion were statistically significant at the fluoride concentration of 0.2% (P<0.01), and the difference among three groups was statistically significant (P<0.01).
CONCLUSION: Patients who frequently use fluoride products should not use pure titanium or cobalt-chromium alloy prosthesis. Patients with these three metal prostheses are not advised to use high concentration fluoride products.