A scanning electron microscopic and polarized light microscopic study of acid-etching of caries-like lesions in human tooth enamel treated with sodium fluoride in vitro.

Types of etching patterns and histological appearances were examined in acid-etched, NaF-treated caries-like lesions of enamel. Etching patterns similar to those for etched-sound enamel were found. Remineralization was limited to the surface zone and superficial portion of the body of the lesion following acid-etching of NaF-treated caries-like lesions.