Abstract
Objective: The effect of disinfectants on the dimensional stability of molding materials was evaluated. Methods: A total of 90 moldings were made using alginate [AG] (n = 45) and addition silicone (SA) (n = 45) using a metal master die and a compatible tray. After washing in running water and drying the molds were subdivided into three groups (n = 15) according to disinfection methods, distilled water [AD], control, chlorhexidine [CLX] and sodium hypochlorite [HS]. The molds were rinsed under running water and they were subjected to air jets. After disinfection of the molds the specimens belonging to CLX and HS were washed in running water and received air jets. The specimens had their diameters measured by means of a digital caliper at two different moments. ANOVA - one way, Tukey and t test (P <0.05) were performed. Results: The specimens showed significant alteration after five days of storage, and AD and sodium hypochlorite group did not change. Conclusion: The most suitable method for disinfecting the GA was the CLX, which in turn is harmful to the SA, being indicated for this HS.