Morphology of the aprismatic enamel: a SEM study of different etching

Using the SEM, 55 longitudinally sectioned deciduous teeth were examined. The specimens were treated with a 37% solution of phosphoric acid and subsequently subdivided into groups in order that they could undergo etching for 1 min., 2 mins., 1 min. + 1 min. A minimal change was obtained with an etching time of 1 min., while an etching time of 2 mins. produced large porosity and deep, evenly distributed fossae. No important differences were seen following intermediated washing.