The aim of this study was to evaluate the effect of the laser irradiation and the presence of fluoride in the remineralizing solution on the remineralization of deminalized enamel. The enamel of ninety human premolars was demineralized artificially. This was then irradiated with a Q-switch Nd-YAG laser and remineralized with two remineralizing solutions, one with and the other without fluoride. To evaluate the mineralized enamel, the mineral content of the enamel was calculated and two acid resistance tests (1. mineral content evaluation after HClO4 immersion, 2. dissolved Ca2+ measurement after lactic acid immersion) were performed.
The results were as follows:
1. In the acid resitance test with HClO4, the presence of fluoride in the remineralizing solution increased the acid resistance of the demineralized enamel.
2. In the acid resistance test with lactic acid,
1) laser irradiation increased the acid resistance of the demineralized enamel,
2) the acid resistance effect of laser irradiation was the same as that of the presence of fluoride in the remineralizing solution, and
3) the highest acid resistance was found in the combined treatment of laser irradiation and remineralization with fluoride.
