Bio-inspired design of dental multilayers: experiments and model

J Mech Behav Biomed Mater. 2009 Dec;2(6):596-602. doi: 10.1016/j.jmbbm.2008.10.009. Epub 2008 Nov 13.

Abstract

This paper combines experiments, simulations and analytical modeling that are inspired by the stress reductions associated with the functionally graded structures of the dentin-enamel-junctions (DEJs) in natural teeth. Unlike conventional crown structures in which ceramic crowns are bonded to the bottom layer with an adhesive layer, real teeth do not have a distinct "adhesive layer" between the enamel and the dentin layers. Instead, there is a graded transition from enamel to dentin within a approximately 10 to 100 microm thick regime that is called the Dentin Enamel Junction (DEJ). In this paper, a micro-scale, bio-inspired functionally graded structure is used to bond the top ceramic layer (zirconia) to a dentin-like ceramic-filled polymer substrate. The bio-inspired functionally graded material (FGM) is shown to exhibit higher critical loads over a wide range of loading rates. The measured critical loads are predicted using a rate dependent slow crack growth (RDEASCG) model. The implications of the results are then discussed for the design of bio-inspired dental multilayers.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Biomechanical Phenomena
  • Biomimetic Materials / chemistry*
  • Ceramics / chemistry
  • Dental Materials / chemistry*
  • Dentin
  • Elastic Modulus
  • Microscopy, Electron, Scanning
  • Models, Biological*
  • Polymers / chemistry
  • Tooth / anatomy & histology*
  • Tooth / physiology*
  • Zirconium / chemistry

Substances

  • Dental Materials
  • Polymers
  • Zirconium
  • zirconium oxide