Effect of saturation on the viscoelastic properties of dentin.

This paper focuses on the analysis and quantitative characterization of the effect of saturation on the viscoelastic properties of human root dentin. Uniaxial compression tests under creep conditions have been performed on root molar dentin with tubules fully saturated with a viscous physiological fluid, as well as samples with non-saturated tubules (dry dentin samples). Blair-Rabotnov (BR) fraction-exponential model is used to characterize the overall viscoelastic properties of dentin and correlate them to the level of saturation. Experimental data are compared with theoretical predictions that interrelate the viscoelastic properties of saturated and dry specimens. The results show that saturation increases the viscous creep strains of dentin, which indicates a reduced capacity for stress relief. The uniaxial compression test under creep conditions, in combination with the BR kernel model, allows us to analyze the creep-relaxation behavior of dentin.