There is a continuing concern over the potential for cross-contamination of viral infections such as AIDS by means of dental impressions. This investigation compared the effects of various viricidal agents on the accuracy of irreversible hydrocolloid and silicone impressions made of single-unit and full mandibular arch models. Measurements on casts made from the treated impressions were compared with the corresponding measurements on casts made from untreated impressions. The results of this study led to the conclusions that there was no preferred disinfectant with respect to dimensional stability for the irreversible hydrocolloid, condensation silicone, or vinyl polysiloxane impression materials tested, and there was no difference in the accuracy of the casts obtained either by spraying with or immersion in any of the disinfectants tested. Therefore using the disinfectants described with either the immersion or spray techniques will not significantly affect the dimensional accuracy of cats made from treated impressions.
