In vivo effect of oral environment on etched enamel: a scanning electron microscopic study.

After etching the enamel in teeth of young children with 50% buffered phosphoric acid and allowing the teeth to remain in the oral environment for a few months, an irregular enamel surface similar to the morphology of recently etched enamel was noted by means of scanning electron microscopy. In addition, the enamel surfaces were covered with plaque. Accordingly, observations by other authors, that etched human enamel takes on a normal appearance after short exposure in the oral cavity, could not be confirmed. However, when the surface of the etched enamel was pumiced, the enamel reacquired both the shine and appearance of non-etched enamel.