[The outermost enamel layer. A comparative scanning electron microscopic study]

Area of Science:

• Paleontology
• Zoology
• Biomineralization

Background:

• The surface of tooth enamel is often described as
• aprismatic
• in scientific literature.
• However, the presence and arrangement of enamel prisms at the surface require further investigation across diverse species.

Purpose of the Study:

• To investigate the structural organization of enamel at the surface and subsurface levels.
• To evaluate the appropriateness of the term
• aprismatic
• for mammalian enamel surfaces.
• To understand how enamel surface structure affects etching patterns.

Main Methods:

• Scanning electron microscopy of enamel surfaces from representative animal species.
• Analysis of enamel structural organization in both surface and subsurface layers.

Main Results:

• Enamel prisms were observed to frequently reach the tooth surface in mammals.
• Prisms are typically packed perpendicularly to the enamel periphery.
• The surface layer exhibits unique structural, physical, and chemical properties.
• The distribution of these surface features explains variations in etching patterns across different areas of the same tooth.

Conclusions:

• The term
• aprismatic
• is considered inappropriate for mammalian enamel surfaces.
• The specific structural organization of the enamel surface layer significantly impacts its properties.
• Understanding enamel surface morphology is crucial for interpreting dental histology and taphonomy.