Variations in Surface Resistance to Enamel Etching

Scanning electron microscopy of clinically sound enamel samples demonstrated two distinct types of perikymata patterns: undulating, and overlapping. When treated with a buffered acetate solution (pH 4.0), the overlapping perikymata were more susceptible to demineralization than the undulating perikymata. Furthermore, in erupted teeth the overlapping forms seemed to be confined primarily to the cervical third of the crown, and in unerupted and partially erupted teeth they were distributed more widely.