[The effect of disinfection on dimension stability of impressions]

To measure the effect of disinfection on dimension stability of alginate, hydrocolloid, and Express putty impressions which were separately immersed in 2% glutaraldehyde solution and 1% 84 disinfector.

Alginate, hydrocolloid, and Express putty impressions were made by 20 mm x 20 mm x 40 mm standards test wares. There were 45 in each kind of test wares. They were divided into 9 groups and 5 pieces in every group. Among them, one group using clear water to flush acted as the matched control, the other groups received respectively 2% glutaraldehyde solution and 1% 84 disinfector immersed in 10 minutes, 20 minutes, 30 minutes. After two hours, the spiral instrument was used to measure the model. The experiment data were analyzed by using the SPSS 11.0 statistic software package.

There was no significant difference in pure water flush and spraying treatment respectively. There was significant difference for alginate and hydrocolloid impression was immersed before and after. There was no significant difference for Express putty silicon rubber impression materials before and after immersion. There was no significant difference in 2% glutaraldehyde solution and 1% 84 disinfector when impressions were immersed in.

Alginate, hydrocolloid and Express putty impressions immersed in 2% glutaraldehyde solution and 1% 84 disinfector separately for 20 minutes does not affect the accuracy, and can be used clinically.