Study of dimensional accuracy of stone models made with different techniques and elastomeric impression materials

Abstract

Objective: The aim of this study was to evaluate and compare the dimensional accuracy of stone models made from three impression techniques (putty/wash, double mix and single mix techniques by using custom acrylic resin trays) and six different elastomeric materials (ExpressTM, Futura ADTM, ClonageTM, Silon APSTM, Optosil/XantoprenTM and Zetaplus/OranwashTM). Methods: Initially, it was obtained a metallic master model with reference points in teeth 33 (LC), 43 (LM), 37 (RC) and 47 (RM) that was used for the accomplishment of the impressions. The distances among the teeth RC-LC, RM-LM, LM-LC and RM-RC were measured. After the molding and specimens procedures have been made, the models were evaluated through a microscope with 30x increase and the distance values statistically analyzed by means of variance analysis with two factors and the means compared by Tukey test (5%). Results and Conclusion: The data showed that addition silicones were the materials which showed the best dimensional accuracy results. And the condensation silicones showed the worst results. It has not been found differences among the three impression techniques. Key words: Elastomeric materials. Impression materials. Impression techniques.