Objectives: CO2 Laser and Diammine-Silver-Fluoride separately have been shown to inhibit demineralization; however the combined effect of the two modalities in inhibiting demineralization of enamel and root has not been investigated. The purpose of this study is to evaluate the effect of CO2 Laser combined with 38% DSF treatment on enamel and root demineralization.
Methods: Eight windows (4 in enamel and 4 in root) approximately 3mmx1mm size were created on fifteen sound extracted human premolars and were randomly assigned to Control (No Treatment), CO2 Laser, DSF, DSF+CO2 Laser treatment groups. 38% DSF was applied for 2 minutes and CO2 laser with a wavelength of 10.6µm, 50HZ repetition rate, 200µs pulse was used. A three day pH cycling scheme for artificial lesion formation and polarized light microscopy for measuring the lesion depths were performed. Factorial ANOVA was employed to test the main effects and interaction.
Results: The mean lesion depths (in μm) for each group were 303.75±12.30 (Control), 224.08 ± 8.61(DSF), 175.22±4.10 (CO2 Laser), 152.74±3.90 (DSF+CO2 Laser) in enamel and 271.30± 11.15 (Control), 219.50± 6.41(DSF), 187.75±4.00 (CO2 Laser), 146.10±5.70 (DSF+CO2 Laser) in root. CO2 Laser and DSF had a statistically significant effect on lesion depth in enamel and root (all p<0.001). The interaction between CO2 Laser and DSF was significant in enamel (p<0.005) but not in root. Individual tooth structure had a statistically significant effect on lesion depth formation in root (p=0.002) but not in enamel.
Conclusion: Combining with CO2 Laser the cariostatic effect of DSF may be doubled.