Improved mineralization of dental enamel by electrokinetic delivery of F- and Ca2+ ions

Abstract This in vitro study evaluated the effects of the infiltration of F- and Ca2+ ions into human enamel by electrokinetic flow (EKF) on the mechanical property and F- content of enamel. Sound human enamel ground sections of unerupted third molars were infiltrated with de-ionized water by EKF and with F- ion by EKF respectively. All samples were submitted to two successive transverse acid-etch biopsies (etching times of 30 s and 20 mins) to quantify F- ion infiltrated deep into enamel. Remarkably, sound enamel showed a large increase in microhardness (MH) after infiltration of NaF (p < 0.00001) and CaCl2 (p = 0.013) by EKF. NaF-EKF increased AEC-LB remineralization compared to controls (p < 0.01). With enamel biopsy technique, at both etching times, more F- ions were found in EKF-treated group than the control group (p << 0.05) and more fluoride was extracted from deeper biopsies in the NaF-EKF group. In conclusion, our results show that EKF treatment is a superior in transporting Ca2+ and F- ions into sound enamel when compared to molecular diffusion, enhancing the mineralization of sound and carious human enamel.