Journal of Materials Science: Materials in Medicine

, Volume 23, Issue 3, pp 677–685

Qualitative assessment of microstructure and Hertzian indentation failure in biocompatible glass ionomer cements

  • Kun V. Tian
  • Peter M. Nagy
  • Gregory A. Chass
  • Pal Fejerdy
  • John W. Nicholson
  • Imre G. Csizmadia
  • Csaba Dobó-Nagy
Article

DOI: 10.1007/s10856-012-4553-2

Cite this article as:
Tian, K.V., Nagy, P.M., Chass, G.A. et al. J Mater Sci: Mater Med (2012) 23: 677. doi:10.1007/s10856-012-4553-2

Abstract

Discs of biocompatible glass ionomer cements were prepared for Hertzian indentation and subsequent fracture analyses. Specifically, 2 × 10 mm samples for reproducing bottom-initiated radial fracture, complemented by 0.2 × 1 mm samples for optimal resolution with X-ray micro tomography (μCT), maintaining dimensional ratio. The latter allowed for accurate determination of volumetric-porosity of the fully cured material, fracture-branching through three Cartesian axes and incomplete bottom-initiated cracking. Nanocomputed tomography analyses supported the reliability of the μCT results. Complementary 2-dimensional fractographic investigation was carried out by optical and scanning electron microscopies on the larger samples, identifying fracture characteristics. The combined 3-D qualitative assessment of microstructure and fractures, complemented by 2-D methods, provided an increased understanding of the mechanism of mechanical failure in these cements. Specifically, cracks grew to link pores while propagating along glass-matrix interfaces. The methodological development herein is exploitable on related biomaterials and represents a new tool for the rational characterisation, optimisation and design of novel materials for clinical service.

Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Kun V. Tian
    • 1
    • 2
    • 3
    • 4
  • Peter M. Nagy
    • 1
  • Gregory A. Chass
    • 2
    • 3
    • 4
    • 5
  • Pal Fejerdy
    • 6
  • John W. Nicholson
    • 7
  • Imre G. Csizmadia
    • 1
    • 2
    • 3
    • 4
    • 8
  • Csaba Dobó-Nagy
    • 1
  1. 1.Materials Science Research Institute, Faculty of DentistrySemmelweis UniversityBudapestHungary
  2. 2.Global Institute of Computational Molecular and Materials Science (GIOCOMMS)TorontoCanada
  3. 3.Global Institute of Computational Molecular and Materials Science (GIOCOMMS)BudapestHungary
  4. 4.Global Institute of Computational Molecular and Materials Science (GIOCOMMS)BeijingChina
  5. 5.Department of Biological and Chemical SciencesQueen Mary University of LondonLondonUK
  6. 6.Department of Prosthetic Dentistry, Faculty of DentistrySemmelweis UniversityBudapestHungary
  7. 7.School of ScienceUniversity of Greenwich, Medway CampusChatham KentUK
  8. 8.Department of ChemistryUniversity of TorontoTorontoCanada