LAUSR

AIM The aim of the present study was to compare the effects of carbon dioxide (CO2 ) laser and casein phosphopeptide amorphous calcium phosphate (CPP-ACP)fluoride varnish on enamel demineralization. METHODS Human teeth were randomly assigned to three groups. The enamel was treated with fluoride varnish, 10.6 μm CO2 laser, or no treatment (control), followed by 9 days of pH cycling. Baseline and final FluoreCam images were used to quantify the area, intensity, and impact of demineralization; cross-sectional microhardness was used to measure the mechanical properties of the enamel. RESULTS There were statistically-significant changes in the area, intensity and impact of demineralization in the control and laser groups (P < 0.05), but not in the fluoride group. The control group showed a significantly greater area and impact of enamel demineralization compared to the fluoride group. The area of demineralization in the laser group was significantly greater than that of the fluoride group. Enamel demineralization of the laser and control groups was comparable. The fluoride group showed statistically-significant harder enamel than the control at 20, 40, and 60 μm depths; the laser group enamel was significantly harder than the control at 20 and 40 μm depths. The fluoride group showed statistically-significant harder enamel than the laser group at 20 μm depth. CONCLUSIONS CPP-ACP fluoride varnish is more effective than CO2 in preventing enamel demineralization.