HISTOLOGY OF ENAMEL
Presented by: N. Robinson(CRRI)
INTRODUCTION Enamel is a higly mineralised structure
covering the anatomic crown of tooth. It is the only tissue that is totally acellular.PHYSICAL PROPERTIES: Colour:- appears bluish white or greyish at the
thick opaque areas & yellow-white at the thin areas reflecting underlying dentin.
ENAMEL
Hardness:- hardest structure of the body i.e.5 to 8khn.Permeability:- selectively permeable.Density:- decreases from the surface of enamel to the
dentino-enamel junction.Thickness:- thickness over the cusps of the molars where it
measures 2.5 mm & incisal edges of incisors where it is 2.0 mm.
CHEMICAL PROPERTIESEnamel is composed of organic & inorganic substancesOrganic --------> 4%Inorganic--------> 96%Water
1) Enamel rods(prisms)2) Rod shealths3) Cementing inter-rod substance.
STRUCTURE OF ENAMEL
Enamel Rod• Longitudinal section
Wavy course of enamel rod• Enamel rods followsa wavy course thefull thickness ofenamel• A more spiral courseis noted at cusps &incisal areas Gnarled enamel
• Enamel Rod: Basic Structural Unit
Cross section of enamel
Microscopic picture of EnamelBrown striae ofRetzius
DEJ, E tufts, E spindles
Enamel lamellae & Cracks
Perikymata (imbrication lines) Are external manifestations
of Retzius striae
Development of Tooth • Tooth and Associated Structures
THANK YOU
Top Related