Study of the Human Tooth Enamel by Electron Microscopy
Abstract
In human teeth, dentin and enamel have a composite structure formed by nano-sized hydroxyapatite crystals (HAP) embedded in a organic matrix. This work describes the study of the structure and chemical composition of human dental enamel by electron microscopy, as well as the defect observed in the center of the enamel crystals, called the “central dark line” (CDL). Images of tooth enamel were taken by high resolution transmission electron microscopy (TEM) (HRTEM) and transmission scanning electron microscopy (STEM) in high-angle scattering annular detection mode (STEM-HAADF). The human teeth used in this work were obtained from orthodontic extractions. The sample preparations were carried out by metallographic methods. The results indicate that CDL was formed during amelogenesis and it is a zone with residues of organic material.
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