Journal of Dental Research, Vol 65, 417-420, Copyright © 1986 by International & American Associations for Dental Research Online Journals
The effects of calcium hydroxide on dentin permeability
D. H. Pashley, S. Kalathoor and D. Burnham
Calcium hydroxide paste was applied to human dentin in vitro to determine
its effects on dentin permeability. Discs of dentin were acid-etched on
both sides to permit determination of their maximum permeability. Smear
layers were then applied to the enamel sides of the discs, thereby reducing
dentin permeability 99%. Topical application of Ca(OH)2 paste to the smear
layer reduced dentin permeability further, to levels 48% below that of
untreated smear layers. When the Ca(OH)2-treated smear layers were exposed
to 6% citric acid for two min, dentin permeability returned to the initial
acid-etched value, demonstrating that Ca(OH)2 offers little protection to
acid challenge. Treatment of acid-etched dentin with Ca(OH)2 produced a
similar reduction in dentin permeability, which was restored to normal
following acid challenge. Thus, Ca(OH)2 is effective at reducing the
permeability of both the smear layer and of acid-etched dentin, in vitro.
