Investigation of the Diffusion of Methylene Blue through Dentin from a Human Tooth

Abstract

The diffusion of an aqueous solution of methylene blue through a section of dentin from a human tooth was studied using diffuse reflectance spectroscopy. A method based on a modified Bouguer–Lambert–Beer law was applied for the quantitative assessment of the rate of diffusion, and experimental data were fitted by the approximation within the free-diffusion model. For the first time, the coefficient of the diffusion of methylene blue through a section of dentin from a human tooth ex vivo was calculated. The mean value of the diffusion coefficient was (6.74 ± 1.32) × 10^–6 cm²/s. The microelement composition of the samples was determined using the X-ray fluorescence method and scanning electron microscopy. The morphology of the surface of various parts of sections of the human tooth, for which the dye diffusion was investigated, was studied.