ENAMEL
,PHYSICAL PROPERTIES OF ENAMEL
• Outer most, densely calcified surrounding the coronal
portion of the tooth.
• It is of ectodermal origin; dentine, cementum and the
dental pulp are of ectomesenchymal origin
• Highly specialized tissue.
• Takes the heavy wear of mastication.
• Does not show a continuous formation throughout the
life.
• Exchange and addition of ions can take place e.g.
fluoride ions
• Hardest tissue in human body
• Variable thickness, thickest at the incisive edges and
cusps of the teeth (2.5 mm) and thinnest at the
cervical margin edge.
• Density and hardness varies in different parts.
,PHYSICAL PROPERTIES OF ENAMEL
• Density decreases from surface of the enamel
to the dentino-enamel junction, from the
incisive edge to cervical margin
• Color of the enamel varies considerably from
yellowish to grey or grayish white or grey-blue
depending on degree of translucency
• Translucency depending on density of enamel
• Brittle
• Elastic modulus of enamel is 19 X 106 pounds
per square inch.
• The breaking stress has an average value of
11000 pounds per square inch.
• The specific gravity of enamel is 2.8.
, Chemical properties (by volume)
• 96 % Inorganic contents.
• 1% Organic matrix
• 3 % Water
,PHYSICAL PROPERTIES OF ENAMEL
• Outer most, densely calcified surrounding the coronal
portion of the tooth.
• It is of ectodermal origin; dentine, cementum and the
dental pulp are of ectomesenchymal origin
• Highly specialized tissue.
• Takes the heavy wear of mastication.
• Does not show a continuous formation throughout the
life.
• Exchange and addition of ions can take place e.g.
fluoride ions
• Hardest tissue in human body
• Variable thickness, thickest at the incisive edges and
cusps of the teeth (2.5 mm) and thinnest at the
cervical margin edge.
• Density and hardness varies in different parts.
,PHYSICAL PROPERTIES OF ENAMEL
• Density decreases from surface of the enamel
to the dentino-enamel junction, from the
incisive edge to cervical margin
• Color of the enamel varies considerably from
yellowish to grey or grayish white or grey-blue
depending on degree of translucency
• Translucency depending on density of enamel
• Brittle
• Elastic modulus of enamel is 19 X 106 pounds
per square inch.
• The breaking stress has an average value of
11000 pounds per square inch.
• The specific gravity of enamel is 2.8.
, Chemical properties (by volume)
• 96 % Inorganic contents.
• 1% Organic matrix
• 3 % Water
