Single bovine enamel particles examined by electron optics

Area of Science:

• Biomineralization
• Materials Science
• Developmental Biology

Background:

• Enamel formation is a complex biomineralization process.
• Understanding enamel maturation is crucial for dental health and biomaterials research.

Purpose of the Study:

• To investigate the mineral phases present during embryonic calf enamel maturation.
• To characterize the chemical and structural changes during enamel development.

Main Methods:

• Density gradient centrifugation of enamel scrapings.
• Transmission electron microscopy (TEM) for structural analysis.
• Electron diffraction for crystallographic information.
• Electron probe micro-analysis (EPMA) for elemental composition and mapping.

Main Results:

• Poorly crystalline hydroxyapatite was the sole identified mineral phase.
• Increasing apatite crystallinity was observed with enamel maturation.
• Molar Ca/P ratios ranged from 1.48 to 1.70, with higher values in lower-density fractions.
• Electron probe mapping revealed non-uniform Ca and P distribution in some particles, potentially linked to carbonate phases.

Conclusions:

• Embryonic calf enamel primarily consists of hydroxyapatite throughout maturation.
• Crystallinity and Ca/P ratios evolve during enamel development.
• Early enamel may contain carbonate phases influencing its composition and structure.