Based on the hydrodynamic hypothesis for tooth thermal pain
a thermo-mechanical model is proposed to simulate dentinal fluid flow under thermal stimulation. It is found that
upon applying the thermal stimulation
other than thermally-induced fluid expansion/contraction
the deformation of dentine micro tubules is responsible for the rapid response of fluid flow in dentinal tubules. The mechanism underlying the difference in neural discharge patterns caused by cooling and those by heating is provided. It is the first time that the hydrodynamic hypothesis proposed by Brännström in 1962 is theoretically demonstrated and perfected.
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