Abstract: Objective To establish a graded standard of mice dental fluorosis. Methods 48 ICR mice were randomly divided into four groups and fed with double-distilled water containing 0, 55, 110 and 220 mg/L of sodium fluoride respectively for 42 days. The changes of the mandibular incisor enamel were recorded by digital
camera everyday. The tooth mineralization was observed with a polarized light microscope. Results The fluorosed teeth enamel experienced changes in different degrees, such as transparency decline, white fine lines, scattered
white spots or patches, white streaks, surface defects and so on. Different fuscescent pero-mineralization of low density could be discovered from adamatine layer in experiment groups by polarized light microscope. The changes of dental fluorosis are divided into 11 degrees. Conclusion The 11-degree graded standard of mice dental fluorosis was established.