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Updated: Jun 27, 2026

Microhardness Measurements on Tooth and Alveolar Bone in Rodent Oral Disease Models
Published on: April 26, 2024
[Relationship between the microstructure and nanohardness of dentin and enamel of human teeth]
Long Chen1, Xi-ping Song, Bei Zhang
1State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China.
Objective:
To investigate the relationship between the nanohardness and microstructure of the dentin and enamel of human teeth.
Methods:
Nano indentation was used to determine the nanohardness of enamel and dentin; TEM and IR were utilized to observe the microstructure and crystalline characteristic.
Results:
The mean nanohardness of the enamel [(4.92 +/- 0.40) GPa] was significantly higher than that of dentin [(1.17 +/- 0.14) GPa]. A large quantity of hydroxyapatite (HA) crystals and uniform lattice stripe were found in enamel but not in dentin.
Conclusions:
The difference of nanohardness between enamel and dentin is related to their density, the inorganic morphology and phase structure.
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