[Dimensional change of elastomeric impressions after disinfectant immersion].

One method to prevent cross-contamination in dental clinic is to immerse the impressions in disinfectants before making master models. This study to evaluate the effect of disinfectants on dimensions of the elastomers namely polyether, condensation silicone, addition silicone and polysulfide, the disinfectant used in this study is 1% Sodium hypochlorite, 0.13% Sporicidin and 10% Gigasept. Being left under room temperature and immersed in distilled water are two types of controls. Dimensional changes can be measured on master model and compared with the brass standard model. The study reveals that the three disinfectants have no effect on vertical dimensions of all four elastomers but have statistically effect on horizontal dimensions of only polyether (p less than .05). It concludes that all the elastomeric impressions except polyether should be immersed in disinfectants before making master models.