Table of Contents
ISRN Biomaterials
Volume 2013 (2013), Article ID 253761, 15 pages
http://dx.doi.org/10.5402/2013/253761
Research Article

Mechanical Properties of Enamel Nanocomposite

1CSIR-Central Glass and Ceramic Research Institute, Kolkata 700032, India
2Thermal Systems Group, ISRO Satellite Centre, Vimanapura, Bangalore 560 017, India
3IBM India Pvt. Ltd., Rajarhat, Kolkata 700156, India
4School of Materials Science and Engineering, Bengal Engineering and Science University, Shibpur, Howrah 711103, India

Received 10 December 2012; Accepted 9 January 2013

Academic Editors: S. M. Ceré, J. Toppari, and X. Wang

Copyright © 2013 Nilormi Biswas et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

For adult Indian premolar teeth, we report for the first time ever the simultaneous evaluations of nanohardness, Young's modulus, and fracture toughness of the enamel nanocomposite. The nanohardness and Young's moduli were evaluated from near the beginning of the middle enamel region to within 10 μm of the dentino-enamel junction (DEJ) and in the dentin region using the nanoindentation technique. The fracture toughness from near the middle of the enamel region to near the DEJ zone was measured using the microindentation technique. The deformation was studied using scanning electron microscopy (SEM) and field emission scanning electron microscopy (FESEM). The relative differences in the extents of biomineralization in the enamel and dentin regions were studied by the energy dispersive X-ray (EDS) technique. The variations of the toughness of the enamel as a function of the toughness of the protein matrix phase have been analyzed which showed that the predicted value of the toughness of the protein present in the nanocomposite was comparable to that of other bioproteins reported in the literature. Further, the work of fracture estimated from the measured value of toughness of the enamel nanocomposite agreed well with the experimental data reported in the literature.