Microstructure of Dental Enamel. I. Organization and Contour of Prisms

Abstract

The differential interference reflected light microscope clearly revealed the microstructures of polished human dental enamel (surface contours, Hunter-Schreger bands and enamel prism boundaries). Height difference in the order of lOOths of a [mu] were detected; Hunter-Schreger bands and prism boundaries were sharply presented. Longitudinal prism sections were softer and polished away faster than transverse sections. The slopes of the Hunter-Schreger bands were transitional cuts, confirming the differential polishing rate of enamel prisms. Secondary elevations in Hunter -Schreger bands were observed for the 1st time. The resultant 3-dimen-sional appearance and color differential supported doubts about the existence of the interprismatic substance and the prismatic sheath. The interprismatic substance appeared to be a continuation of the substance of the adjacent enamel prism. The prismatic sheath was a prismatic boundary relief. These conclusions are confirmed by fringe displacement under reflected multiple ray interference microscopy.