Study on Selective Removal of Caries using Laser Absorption Properties

Objectives:In this study, to examine the color-related specificity of laser absorption at various wavelengths, we irradiated specimens, which had been stained with the caries-detecting solutions (CDS) with a laser, measured the energy, and calculated the rate of absorption. Methods:We used a P-LASER as diode laser, an Erwin AdvErL as Er:YAG laser and a PanalasC05 as CO₂ laser. One drop of the CDS was placed on filter paper and artificial caries dentin specimens, and dried. Then, we measured the energy penetrating the specimens using a laser power meter. We calculated the absorption rate of staining-related irradiation energy, regarding values obtained by laser irradiation without the specimens as controls. The data were statistically analyzed using one-way variance analysis and Scheffe's test. Results:When the filter paper penetrated, Green showed the highest absorption rate of the diode laser. When the artificial caries dentin penetrated, Green showed the highest absorption rate of the diode laser. There were significant differences between the absorption rate for red and purple those for green. Er:YAG laser and CO₂ laser did not show any significant color-related differences in its absorption rate. Conclusions:These findings suggest that caries staining with green CDS for diode laser treatment facilitates selective removal.