Disinfectant-fixing combined solution for alginate impression using sodium hypochlorite.

Abstract

We prepared a disinfectant-fixing combined solution (NCK) for an alginate impression containing 1%NaClO-0.2%CaCl₂-1%K₂SO₄. Calcium chloride (CaCl₂) inhibited swelling of the impression at a concentration of 0.15%, therefore, the surface roughness of the stone cast was improved. Potassium sulfate (K₂SO₄) itself showed a property that inhibited swelling of the impression. With calcium chloride, K₂SO₄ stabilized the size of the impression for long hours by inhibiting consecutive shrinking of the impression, which was attributed to the uptake of calcium into the impression. Changes in sizes of the impression immersed in a 1%NaClO solution for 60 min and surface roughness of the stone cast set against it were 0.78% and 1.45μm (mean values of 4 products) respectively. However, those values were reduced to -0.16% and 1.04 μm when the impression was immersed in a solution of NCK. The results showed that the values for the solution of NCK were significantly lower than the values for the solution of 1%NaClO.

Accordingly, NCK may be an excellent disinfectant-fixing combined solution for fixing an alginate impression and stabilizing the size of it.