The aim of this investigation was to assess dimensional changes of impressions made of
a newly developed polyether material following immersion disinfection.
A cylindrical specimen was impressed using a monophase impression made of
Impregum® Penta Soft, Impregum® Penta, two experimental polyether materials and an
A-silicone. The impressions were immersed for 10 and 60 minutes in water and
Impresept®, a control group without immersion was added.
Cylindrical die models made of stone were measured by means of a computer controlled
three-dimensional scanning device to asses the changes in dimension and form
compared to the original. Results were analysed using M-ANOVA using a significance
level of p = 0.05.
Significant (p<0.05) differences were found on the material factor. No significant
differences were found on the impression medium. Differences in time of the immersion
were found to be highly significant (p<0.001). The dimensional changes found in the
material groups range from 0.05 %lin. to 0.13 %lin. and keep inside the specifications
of DIN 13913. Thus, they are of no relevance to clinical procedures. It can be
concluded, that polyether impressions made of the classical Impregum® and the newly
developed material generation may be disinfected without clinically relevant
dimensional changes provided that the proposed immersion time is not exceeded.
