Journal of Dental Research, Vol 65, 154-157, Copyright © 1986 by International & American Associations for Dental Research Online Journals
Measurement of the permeability of dental enamel and its variation with depth using an electrochemical method
P. M. Hoppenbrouwers, H. P. Scholberg and J. M. Borggreven
To investigate the permeability of the dental enamel of erupted and
unerupted human pre-molars and its variation with depth, we determined the
resistivity of successive 100-micron-thick layers. The electrical
resistance of halved tooth crowns at zero Hertz, which according to
Scholberg et al. (1982, 1984) is inversely related to the permeability, was
measured before and after removal of successive enamel layers from the
outer surface toward the dentino-enamel junction (D.E.J.). The resistivity
of the successive enamel layers increased from the D.E.J. toward the outer
surface in approximately the same way in erupted as well as in unerupted
pre-molars, except within the outermost layer of 100 to 200 microns
thickness. The resistivity of this layer in erupted pre-molars was
considerably higher than that in unerupted pre-molars, which may be due to
post-eruptive mineralization.
