Electric current produced by corrosion of metals or used for diagnostic or therapeutic purposes has to pass through the dentin to reach the pulp. The electric resistance of the dentin, which influences the dentinal current intensity, is poorly documented in the literature. In this study 140 cylindrical dentin samples of human teeth were collected from four different regions of the tooth crown and their specific electrical resistance was measured. The recorded values vary with the orientation of the dentinal tubules ranging between 12.5 ohms and ohms. The linear temperature coefficient of the specific resistance is -0.0132 degrees C-1 for the temperature interval of 20 to 34 degrees C. It is assumed that the mechanism underlying electric conduction in dentin is related to the transport of ions in the dentinal fluid.
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Bioelectromagnetics
January 2025
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