Abstract
Mineral density of three different parts along the dentinal tubul in each of cross sections cut according to their distance from the incisal apex was determined. The density of the dentin was almost independent of the time when the dentin was produced and dependent on the resion where the dentin was formed. The density of the dentin increased as the region approached from the edge to the apex of the incisor. This result suggests the difference in activity of odontoblasts to participate in formation of the dentin in their regions.
