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[Evaluation of acid diffusion and fluoride selective electrode to measure the total fluoride in toothpastes]
Xiao-Ling Wang1, Chuo-Yue Cheng, Yao Ge
1Dept. of Preventive Dentistry, Peking University School of Stomatology, Beijing 100081, China.
Objective:
To evaluate the reliability of a method of measuring the total fluoride in fluoride-containing toothpastes with acid diffusion and fluoride selective electrode.
Methods:
Four brands of commercially available non-fluoride toothpastes and fluoride-containing toothpastes were sampled. Fluoride was extracted from the toothpastes in 2 mol/L HC10(4) at room temperature overnight and then subjected to the measurement with fluoride electrode.
Results:
Fluoride recovery of the non-fluoride toothpastes containing calcium as abrasive by this method was 99.5%-100.5%, more than 94% of total fluoride was measured from the marketed fluoride toothpastes, and the variation coefficient of this method was less than 1.54%. While the abrasive was silicon, the fluoride recovery of the non-fluoride toothpastes was 83.4%, and 89.7% of total fluoride was measured from the marketed fluoride-containing toothpastes.
Conclusion:
The amount of total fluoride in the calcium containing toothpaste can be detected simply and accurately measured by acid diffusion and fluoride selective electrode.
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