Length and shape of enamel crystals

Area of Science:

• Biomineralization
• Materials Science
• Crystallography

Background:

• Enamel apatite crystals form the structural basis of dental enamel.
• Understanding crystal morphology and arrangement is crucial for comprehending enamel properties.

Purpose of the Study:

• To develop an original method for fractionating and preparing isolated enamel apatite crystals of homogeneous size.
• To investigate the morphology, size, flexibility, and arrangement of enamel apatite crystals during formation and maturation.

Main Methods:

• Development of a novel fractionation and preparation technique for isolated enamel apatite crystals.
• Microscopic visualization and measurement of crystal curvatures and growth patterns.
• Analysis of crystal fusion and shape changes during enamel maturation.

Main Results:

• Enamel apatite crystals were demonstrated to be at least 100 microns long and exhibit flexibility.
• Crystal curvatures were visualized and measured, explaining the irregular prism paths.
• Crystal growth, branching, fusion, and shape transformations (pyramidal to rod-like) were observed during maturation, leading to close packing.

Conclusions:

• The developed method allows for the isolation and characterization of homogeneous enamel apatite crystals.
• The findings support the hypothesis of continuous crystallites from the dentino-enamel junction to the enamel surface.
• Crystal morphology and arrangement changes during maturation are key to enamel's structural integrity.