Dimensionsänderung von Abformmassen auf Polyetherbasis nach Desinfektion

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.