Laser-fluoride effect on root demineralization

Abstract

Although the individual cariostatic effects of laser and fluoride have been shown, the combined effect of CO 2 laser and fluoride on root demineralization remains uncertain and was the main aim of this study. By using a pH-cycling system and Polarized Light Microscopy, we demonstrated the synergistic effect of fluoride combined with CO 2 laser treatment on reducing root demineralization. The mean lesion depths (in μm) for each group were 160 ± 14 (Control), 113 ± 8 (Laser treatment alone), 111 ± 6 (Fluoride treatment alone), and 25 ± 7 (Fluoride followed by laser treatment). A significant laser-enhanced fluoride uptake, characterized by the ToF-SIMS analysis, was revealed by the 37% and 400% increments in loosely and firmly bound fluorides (both p < 0.002) in laser-irradiated areas, compared with the non-irradiated controls. In conclusion, there is a significant synergistic effect of combined CO 2 laser and fluoride treatment on the inhibition of root demineralization, possibly due to laser-enhanced fluoride uptake in the root.