Nanoindentation in teeth: the influence of experimental conditions on local mechanical properties

Griselda María Guidoni (1) , Julia Denkmayr (2) , Thomas Schöberl (2, 3) , Ingomar Jäger (2)

1 Department Materialphysik
2 Department Materialphysik
3 ESI - Erich Schmid Institute of Materials Science

The influence of various experimental conditions on the elastic modulus and hardness of human intertubular dentin was studied using instrumented nanoindentation at room temperature. The conditions studied were: dry (chemically dehydrated) versus wet (prepared and nanoindented under HBSS), the influence of long-term storage under HBSS at ca. 4oC, and the influence of deep-freezing under dry and wet conditions, respectively. The reversibility of chemical dehydration and the consequences of multiple deep-freezing cycles were also investigated. Two premolars of a twelve-years-old human male were chosen for evaluation. The absolute values of the mechanical properties differed by a factor of ~ 2 and ~ 3 between dry and wet state, whereas trends were conserved. Deep-freezing wet dentin samples deteriorated their mechanical properties by about 20 to 28%, whereas dehydrated samples suffered no damage. This may be due to the mechanical damage by the volume increase of water freezing inside the tubules.

Mots clés: Physical Sciences

Griselda María Guidoni, Julia Denkmayr, Thomas Schöberl, Ingomar Jäger. Nanoindentation in teeth: the influence of experimental conditions on local mechanical properties. Philosophical Magazine, 2006, 86 (33-35), pp.5705-5714. ⟨10.1080/14786430600599757⟩. ⟨hal-00513665⟩