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Updated: Feb 6, 2026
07:57
Sampling and Pretreatment of Tooth Enamel Carbonate for Stable Carbon and Oxygen Isotope Analysis
Published on: August 15, 2018
14.8K
Human enamel rod presents anisotropic nanotribological properties
Yeau-Ren Jeng1, Tsung-Ting Lin, Hsiu-Ming Hsu
1Department of Mechanical Engineering of National Chung Cheng University, Chia-Yi, 62100, Taiwan. imeyrj@ccu.edu.tw
Journal of the Mechanical Behavior of Biomedical Materials
|March 15, 2011
Summary
Human enamel nanohardness and elastic modulus are highest at the rod head, decreasing towards the dentino-enamel junction. This variation correlates with calcium content and impacts friction and wear properties.
Area of Science:
- Biomaterials science
- Nanotechnology
- Dental materials science
Background:
- Human enamel's complex ultrastructure influences its mechanical properties.
- Understanding nanomechanical and nanotribological properties is crucial for dental applications.
Purpose of the Study:
- To investigate the nanomechanical and nanotribological properties of human enamel rods.
- To correlate these properties with ultrastructure and elemental composition.
Main Methods:
- Atomic Force Microscopy (AFM) combined with nanoindentation.
- Probing mechanical properties (nanohardness, elastic modulus) and tribological properties (friction, nanowear).
- Analysis across various section planes and positions of enamel rods.
Main Results:
- Nanohardness and elastic modulus are significantly higher in the enamel rod head compared to the tail and axial-sectional plane.
- Mechanical properties decrease from the enamel surface towards the dentino-enamel junction, correlating with calcium content.
- Friction coefficient and nanowear exhibit an inverse trend to hardness along the enamel rod axis.
Conclusions:
- Human enamel nanomechanical and nanotribological properties vary significantly with position and ultrastructure.
- Results provide a reference for developing advanced dental restorative materials.
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