人牙本质弹性常数的共振超声光谱测量

Resonant ultrasound spectroscopy measurements of the elastic constants of human dentin.

作者信息

Kinney J H, Gladden J R, Marshall G W, Marshall S J, So J H, Maynard J D

机构信息

Division of Biomaterials and Bioengineering, Department of Preventive and Restorative Dental Sciences, University of California, Mail Stop 0758, San Francisco, CA 94143, USA.

出版信息

J Biomech. 2004 Apr;37(4):437-41. doi: 10.1016/j.jbiomech.2003.09.028.

DOI:10.1016/j.jbiomech.2003.09.028

PMID:14996555

Abstract

The technique of resonant ultrasound spectroscopy (RUS) was used to measure the second-order elastic constants of hydrated human dentin. Specimens were placed between two transducers, and the resonant frequencies of vibration were measured between 0.5 and 1.4 MHz. The elastic constants determined from the measured resonant frequencies in hydrated dentin exhibited slight hexagonal anisotropy, with the stiffest direction being perpendicular to the axis of the tubules (E11 = 25.1GPA) This hexagonal anisotropy was small (E33/E11 = 0.92), and almost disappeared when the specimens were dried. In addition, there was a pronounced anisotropy in the Poisson's ratio of wet dentin: v21 = 0.45; v31 = 0.29. With drying in air, this anisotropy vanished: v21 = v31 = 0.29. The isotropic Young's modulus of dried dentin was 28.1 GPa. RUS shows promise for determining the elastic constants in mineralized tissues.

摘要

采用共振超声光谱（RUS）技术测量水合人牙本质的二阶弹性常数。将标本置于两个换能器之间，测量0.5至1.4MHz之间的振动共振频率。根据水合牙本质中测量的共振频率确定的弹性常数表现出轻微的六方各向异性，最硬的方向垂直于小管轴（E11 = 25.1GPA）。这种六方各向异性较小（E33/E11 = 0.92），当标本干燥时几乎消失。此外，湿牙本质泊松比存在明显各向异性：v21 = 0.45；v31 = 0.29。在空气中干燥后，这种各向异性消失：v21 = v31 = 0.29。干燥牙本质的各向同性杨氏模量为28.1GPa。RUS在确定矿化组织中的弹性常数方面显示出前景。