Abstract: Objective：Regenerating enamel-like mineralized tissue on the demineralized enamel surface by constructing an enamel mineralization model in vitro. Methods： The bottom end of the three-way tube is closed, and CaCl2 agarose gel was placed in the tube to separate the upper and side end, and acid-etched enamel slice was placed on the gel surface from upper end. A 2 mm thick layer of agarose gel containing CaCl2 was used to cover acid-etched enamel slice, followed by a 2 mm thick layer of ion-free agarose gel. Then Na2HPO4 solution (or containing sodium fluoride) was added onto the ion-free gel surface. CaCl2 solution was added to the side tube and was connected to the anode. Na2HPO4 solution was connected to the cathode, and 40 mA DC electric field was applied. Results： When no current was applied, a small amount of uneven banded crystals formed on the demineralized enamel surface without fluoride ions; Hexagonal and densely packed flake crystals formed on the demineralized enamel surface with fluoride ions. In the case of a DC electric field, with no fluorine ions, the amount of crystal deposited on the enamel surface increases, and the morphology of the crystal changes to a plate crystal. With fluoride ion, the surface of the demineralized enamel forms a nanorod-like crystal and is parallel to each other which was similar to enamel prisms. Conclusions： The agarose gel mineralization system loaded with calcium phosphate and fluoride ions aided with an electric field can biomimetic the process of enamel mineralization, which can deposit an enamel prism-like crystal structure on the demineralized enamel surface.

Key words: agarose gel, biomimetic mineralization, enamel, DC electric field