Effect of Organic Ions on Solubility of Enamel and Dentin in Acid Buffers

Abstract

The effect of the addition of 19 different acids to decalcifying buffers on the solubility rates of enamel and dentin over the pH range 2.6-6.0 was determined. The capacity of an acidic environment to decalcify enamel and dentin could be significantly increased or decreased by the addition of certain acid ions. In this respect enamel appears to be considerably more sensitive to the composition of the decalcification medium than dentin, whose solubility appears to be influenced only by those ions which show the strongest effects with enamel. With respect to the solubility reductions observed, the following have been noted The monobasic acids produce little or no effect at any of the pH levels tested. The dibasic acids demonstrate moderate effects. The tribasic acids and EDTA show strong effects. The presence of additional polar groups, such as amino or hydroxy, in these acids considerably enhance their capacity to reduce solubility. From the contrasting findings with the homologues, aspartic and glutamic acids, and the sterioisomers, maleic and fumaric acids, there is an indication that the spatial arrangement of functional groups is important in determining the capacity for reduction.