PERMEABILITY OF BIOLOGICAL AND SYNTHETIC MOLECULES THROUGH DENTIN

The diffusion through dentine by a number of biological and synthetic molecules, including resins and dyes, is reported. In vitro measuremen ts were derived by experiments with a modified 'split-chamber device'. Diffusion was found to be indirectly proportional to dentine thicknes s for all molecules. Permeability of water-soluble molecules and ethan ol-soluble molecules was proportional to the molecular weights, except for fluorescein, hydrogen peroxide (H2O2) and urethane dimethacrylate . The resin components tested are not soluble enough in an aqueous med ium to diffuse through 0-5 mm dentine at sufficient concentrations to cause cytotoxicity to pulpal cells.