Aim: The aim of this study was to evaluate the influence of immersion period in two disinfectant solutions on dimensional change of four elastomeric impression materials. Materials and methods: Four representative materials of each class of elastomers: Xantopren (polydimethylsiloxane-PDS), Express (polyvinyl siloxane-PVS); Permlastic (polysulfide-PS) and Soft Impregum (polyether-EP) were mixed according to manufacturers' instructions and then inserted into a metal matrix prepared according to the specification of ISO 4823. The molds were removed from the matrix after 7 minutes and immersed in disinfectant solutions (sodium hypochlorite 0.5 and 2% glutaraldehyde) for 5, 10, 20, 30 and 60 minutes (n = 7), except the control group, which was not immersed. Once removed from solutions, the test samples were washed in water for 15 seconds, dried and measured three times, using a comparative optical microscope, with accuracy of 0.0005 mm. The analysis of variance with three criteria and Tukey's test with significance level of 5% showed that differences in linear dimensions of the materials analyzed were not statistically significant (p > 0.05) after soaking in sodium hypochlorite 0.5 and 2% glutaraldehyde, for the tested periods of time. 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