全部 标题 作者
关键词 摘要

OALib Journal期刊
ISSN: 2333-9721
费用:99美元

查看量下载量

相关文章

更多...

Mechanical Properties of Enamel Nanocomposite

DOI: 10.5402/2013/253761

Full-Text   Cite this paper   Add to My Lib

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. 1. Introduction Tooth is a microscopically functionally graded calcium phosphate based natural biocomposite material (Figure 1). Furthermore, tooth has also a hierarchical architecture, for example, from macrostructure to microstructure to nanostructure (Figure 1). The tooth is composed of mainly the hard enamel, the more ductile dentin, and a soft connective tissue, the dental pulp. Enamel is the hardest structure in the human body with approximately 95?wt% hydroxyapatite (HAP). On the other hand, dentine possesses a porous structure and is made up of 70% inorganic material (i.e., HAP), 20% organic materials (i.e., collagen fiber), and 10% water by weight. The enamel microstructure shows different orientations of closely packed enamel prisms or rods. These rods are encapsulated by an organic protein called enamel sheath. Further, the prisms or rods consist of nanosize inorganic HAP crystals with different orientations inside. On the other hand, the dentine has a collagen matrix reinforced with HAP nanocrystal retained as layer by layer. The composite bed of dentine also has dentine tubules and channel-like microstructures which supply the nutrition from the pulp region to the crown part of the teeth. In contrast, the interface between the enamel and dentin junction (DEJ) is arranged with

References

[1]  S. N. Bhaskar, Orban's Oral Histology and Embryology, Harcourt Brace and Company, Singapore, 11th edition, 1999.
[2]  V. Imbeni, J. J. Kruzic, G. W. Marshall, S. J. Marshall, and R. O. Ritchie, “The dentin-enamel junction and the fracture of human teeth,” Nature Materials, vol. 4, no. 3, pp. 229–232, 2005.
[3]  L. H. He and M. V. Swain, “Enamel-A functionally graded natural coating,” Journal of Dentistry, vol. 37, no. 8, pp. 596–603, 2009.
[4]  Y. L. Chan, A. H. W. Ngan, and N. M. King, “Nano-scale structure and mechanical properties of the human dentine-enamel junction,” Journal of the Mechanical Behavior of Biomedical Materials, vol. 4, no. 5, pp. 785–795, 2011.
[5]  S. Marwan, A. Haik, A. Trinkle, D. Garcia, and F. Yang, “Investigation of the nanomechanical and tribological properties of dental materials,” International Journal of Theoretical and Applied Multiscale Mechanics, vol. 1, no. 1, pp. 1–15, 2009.
[6]  S. F. Ang, E. L. Bortel, M. V. Swain, A. Klocke, and G. A. Schneider, “Size-dependent elastic/inelastic behavior of enamel over millimeter and nanometer length scales,” Biomaterials, vol. 31, no. 7, pp. 1955–1963, 2010.
[7]  F. Lippert, D. M. Parker, and K. D. Jandt, “Susceptibility of deciduous and permanent enamel to dietary acid-induced erosion studied with atomic force microscopy nanoindentation,” European Journal of Oral Sciences, vol. 112, no. 1, pp. 61–66, 2004.
[8]  J. Ge, F. Z. Cui, X. M. Wang, and H. L. Feng, “Property variations in the prism and the organic sheath within enamel by nanoindentation,” Biomaterials, vol. 26, no. 16, pp. 3333–3339, 2005.
[9]  L. Angker, M. V. Swain, and N. Kilpatrick, “Micro-mechanical characterisation of the properties of primary tooth dentine,” Journal of Dentistry, vol. 31, no. 4, pp. 261–267, 2003.
[10]  J. Zhou and L. L. Hsiung, “Depth-dependent mechanical properties of enamel by nanoindentation,” Journal of Biomedical Materials Research A, vol. 81, no. 1, pp. 66–74, 2007.
[11]  I. R. Spears, “A three-dimensional finite element model of prismatic enamel: a re-appraisal of the data on the young's modulus of enamel,” Journal of Dental Research, vol. 76, no. 10, pp. 1690–1697, 1997.
[12]  Z. H. Xie, E. K. Mahoney, N. M. Kilpatrick, M. V. Swain, and M. Hoffman, “On the structure-property relationship of sound and hypomineralized enamel,” Acta Biomaterialia, vol. 3, no. 6, pp. 865–872, 2007.
[13]  Z. Xie, M. Swain, P. Munroe, and M. Hoffman, “On the critical parameters that regulate the deformation behaviour of tooth enamel,” Biomaterials, vol. 29, no. 17, pp. 2697–2703, 2008.
[14]  F. R. Reich, B. B. Brenden, and N. S. Porter, Ultrasonic Imaging of Teeth, Batelle Memorial Institue, Washington, DC, USA, 1967.
[15]  M. Staines, W. H. Robinson, and J. A. A. Hood, “Spherical indentation of tooth enamel,” Journal of Materials Science, vol. 16, no. 9, pp. 2551–2556, 1981.
[16]  R. Rohanizadeh, F. S. M. Ismail, N. M. Kilpatrick, M. V. Swain, and E. K. Mahoney, “Mechanical properties and microstructure of hypomineralised enamel of permanent teeth,” Biomaterials, vol. 25, no. 20, pp. 5091–5100, 2004.
[17]  L. H. He, N. Fujisawa, and M. V. Swain, “Elastic modulus and stress-strain response of human enamel by nano-indentation,” Biomaterials, vol. 27, no. 24, pp. 4388–4398, 2006.
[18]  J. Zhou and L. L. Hsiung, “Biomolecular origin of the rate-dependent deformation of prismatic enamel,” Applied Physics Letters, vol. 89, no. 5, pp. 051904(1)–051904(3), 2006.
[19]  A. Reuss and Z. Angew, “Berechnung der Flie grenze von Mischkristallen auf Grund der Plastizit tsbedingung für Einkristalle,” ZAMM- Journal of Applied Mathematics and Mechanics, vol. 9, pp. 49–58, 1929.
[20]  W. Voigt, “Uber die Beziehung zwischen den beiden Elastizitatskonstanten isotroper Korper,” Philosophical Transactions, vol. 38, pp. 573–587, 1889.
[21]  R. Hill, “The elastic behaviour of a crystalline aggregate,” Proceedings of the Physical Society A, vol. 65, no. 5, pp. 349–354, 1952.
[22]  R. G. Craig, F. A. Peyton, and D. W. Johnson, “Compressive properties of enamel dental cements and gold,” Journal of Dental Research, vol. 40, no. 5, pp. 936–945, 1961.
[23]  S. T. Rasmussen, R. E. Patchin, D. B. Scott, and A. H. Heuer, “Fracture properties of human enamel and dentin,” Journal of Dental Research, vol. 55, no. 1, pp. 154–164, 1976.
[24]  R. Hassan, A. A. Caputo, and R. F. Bunshah, “Fracture toughness of human enamel,” Journal of Dental Research, vol. 60, no. 4, pp. 820–827, 1981.
[25]  H. H. K. Xu, D. T. Smith, S. Jahanmir et al., “Indentation damage and mechanical properties of human enamel and dentin,” Journal of Dental Research, vol. 77, no. 3, pp. 472–480, 1998.
[26]  H. Fong, M. Sarikaya, S. N. White, and M. L. Snead, “Nano-mechanical properties profiles across dentin-enamel junction of human incisor teeth,” Materials Science and Engineering C, vol. 7, no. 2, pp. 119–128, 2000.
[27]  S. N. White, W. Luo, M. L. Paine, H. Fong, M. Sarikaya, and M. L. Snead, “Biological organization of hydroxyapatite crystallites into a fibrous continuum toughens and controls anisotropy in human enamel,” Journal of Dental Research, vol. 80, no. 1, pp. 321–326, 2001.
[28]  L. H. He and M. V. Swain, “Contact induced deformation of enamel,” Applied Physics Letters, vol. 90, no. 17, pp. 171916(1)–171916(3), 2007.
[29]  S. Park, D. H. Wang, D. Zhang, E. Romberg, and D. Arola, “Mechanical properties of human enamel as a function of age and location in the tooth,” Journal of Materials Science, vol. 19, no. 6, pp. 2317–2324, 2008.
[30]  S. Park, J. B. Quinn, E. Romberg, and D. Arola, “On the brittleness of enamel and selected dental materials,” Dental Materials, vol. 24, no. 11, pp. 1477–1485, 2008.
[31]  D. Bajaj, A. Nazari, N. Eidelman, and D. D. Arola, “A comparison of fatigue crack growth in human enamel and hydroxyapatite,” Biomaterials, vol. 29, no. 36, pp. 4847–4854, 2008.
[32]  S. Roy and B. Basu, “Mechanical and tribological characterization of human tooth,” Materials Characterization, vol. 59, no. 6, pp. 747–756, 2008.
[33]  S. F. Ang, T. Scholz, A. Klocke, and G. A. Schneider, “Determination of the elastic/plastic transition of human enamel by nanoindentation,” Dental Materials, vol. 25, no. 11, pp. 1403–1410, 2009.
[34]  D. Bajaj and D. Arola, “Role of prism decussation on fatigue crack growth and fracture of human enamel,” Acta Biomaterialia, vol. 5, no. 8, pp. 3045–3056, 2009.
[35]  S. K. Padmanabhan, A. Balakrishnan, M. C. Chu, T. N. Kim, and S. J. Cho, “Micro-indentation fracture behavior of human enamel,” Dental Materials, vol. 26, no. 1, pp. 100–104, 2010.
[36]  Y. R. Jeng, T. T. Lin, H. M. Hsu, H. J. Chang, and D. B. Shieh, “Human enamel rod presents anisotropic nanotribological properties,” Journal of the Mechanical Behavior of Biomedical Materials, vol. 4, no. 4, pp. 515–522, 2011.
[37]  S. N. White, V. G. Miklus, P. P. Chang et al., “Controlled failure mechanisms toughen the dentino-enamel junction zone,” Journal of Prosthetic Dentistry, vol. 94, no. 4, pp. 330–335, 2005.
[38]  X. D. Dong and N. D. Ruse, “Fatigue crack propagation path across the dentinoenamel junction complex in human teeth,” Journal of Biomedical Materials Research A, vol. 66, no. 1, pp. 103–109, 2003.
[39]  V. Imbeni, J. J. Kruzic, G. W. Marshall, S. J. Marshall, and R. O. Ritchie, “The dentin-enamel junction and the fracture of human teeth,” Nature Materials, vol. 4, no. 3, pp. 229–232, 2005.
[40]  W. C. Oliver and G. M. Pharr, “Improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments,” Journal of Materials Research, vol. 7, no. 6, pp. 1564–1580, 1992.
[41]  G. R. Anstis, P. Chantikul, B. R. Lawn, and D. B. Marshall, “A critical evaluation of indentation techniques for measuring fracture toughness: I, direct crack measurements,” Journal of the American Ceramic Society, vol. 64, no. 9, pp. 533–538, 1981.
[42]  S. W. Tsai, “Structural behavior of composites materials,” 1964, NSA-CR-71.
[43]  H. Gao, B. Ji, I. L. J?ger, E. Arzt, and P. Fratzl, “Materials become insensitive to flaws at nanoscale: lessons from nature,” Proceedings of the National Academy of Sciences of the United States of America, vol. 100, no. 10, pp. 5597–5600, 2003.
[44]  H. S. Kim, “On the rule of mixtures for the hardness of particle reinforced composites,” Materials Science and Engineering A, vol. 289, no. 1-2, pp. 30–33, 2000.
[45]  J. B. Park and R. S. Lakes, BioMaterials: An Introduction, in Ceramic Implant Materials, 1979, Plenum Press, New York, Ny, USA, 1992.
[46]  A. Franck, G. Cocquyt, P. Simoens, and N. De Belie, “Biomechanical properties of Bovine claw horn,” Biosystems Engineering, vol. 93, no. 4, pp. 459–467, 2006.
[47]  C. Robinson, J. Kirkham, and R. C. Shore, Dental Enamel Formation to Destruction, CRC Press, Boca Raton, Fla, USA, 1995.
[48]  Y. W. Fan, Z. Sun, R. Wang, C. Abbott, and J. Moradian-Oldak, “Enamel inspired nanocomposite fabrication through amelogenin supramolecular assembly,” Biomaterials, vol. 28, no. 19, pp. 3034–3042, 2007.
[49]  J. McKittrick, P. Y. Chen, L. Tombolato et al., “Energy absorbent natural materials and bioinspired design strategies: a review,” Materials Science and Engineering C, vol. 30, no. 3, pp. 331–342, 2010.
[50]  B. W. Li, H. P. Zhao, X. Q. Feng, W. W. Guo, and S. C. Shan, “Experimental study on the mechanical properties of the horn sheaths from cattle,” Journal of Experimental Biology, vol. 213, no. 3, pp. 479–486, 2010.

Full-Text

comments powered by Disqus

Contact Us

service@oalib.com

QQ:3279437679

WhatsApp +8615387084133

WeChat 1538708413