Quality of stone dies produced by different impression materials. A comparative study of impression techniques

A comparison was made of the ability of different impression materials to depict precision made steel blocks. Stone dies poured into such impressions were studied concerning their hardness, dimensional accuracy, detail reproduction, and surface reproduction. The dies were produced in the impression material only to a small extent, with the exception of their surface roughness. Differences between impression materials are otherwise small. The advantages of two-phase alginates over standard alginates lie in the impression technique rather than in the characteristics of the material.