NANOMECHANICAL BEHAVIOR OF HUMAN MOLARS SOAKED IN SLIGHT ACID SOLUTIONS

作者：Fang Te Hua; Chang Win Jin^*; Kang Shao Hui; Chu Chia Chun

来源：Modern Physics Letters B, 2009, 23(26): 3115-3124.

DOI：10.1142/S0217984909021168

• Nanoindentation
• teeth
• hydroxyl apatite
• biomechanics

This paper studied the mechanical and chemical properties of hydroxyl apatite (HA) crystal structure in the teeth when human molars were soaked in slight acid solution. First, we soaked the ground and polished molars respectively in the liquor of 30 wt.% H(2)CO(3) and the liquor of 30 wt.% H(2)O(2) for 10, 20, or 60 minutes. Next, we used a nanoindenter to measure the hardness and Young's modulus. Finally, we used a scanning electron microscope (SEM) coupled with energy dispersive spectroscopy (EDS) to analyze the variation of Ca, P and Na in teeth, a high resolution transmitting electron microscope (HRTEM) to observe the arrangement of crystallization phase of HA, and X-ray diffraction (XRD) to analyze the crystallinity of the hexagonal phase of HA. The results showed that the demineralization phenomenon of the calcium-phosphorous compound in teeth made the teeth reduce sharply in hardness and Young's modulus after they were soaked in the two slight acid solutions for 10 minutes, but the re-mineralization phenomenon made the hardness and Young's modulus ascend gradually when the time lasted longer. With the same period of time, the teeth soaked in H(2)CO(3) were lower in the hardness and Young's modulus than that in H(2)O.

• 出版日期2009-10-20