EVALUATION OF SURFACE ACCURACY AND DIMENSIONAL STABILITY OF TWO SILICONE BASED IMPRESSION MATERIALS SUBJECTED TO CHEMICAL DISINFECTION BY THREE DIFFERENT IMMERSION DISINFECTANTS: AN IN VITRO STUDY

Abstract

Aim: The aim of present was to study the surface changes and dimensional stability of two silicone based impression materials viz; addition silicone and  polyether impression materials subjected to chemical disinfection by three different immersion disinfectants viz; 0.525% sodium hypochlorite, 0.3% benzalkonium chloride and 2% Glutaraldehyde at different time intervals.
Materials and methodology: 40 samples of 2x2cm were prepared from Aquasil Ultra (Group 1) and Impregum Garant (Group 2) impression materials by placing it between two microscopic slides to an even surface. Ten samples of each group were subjected to disinfection by 0.525% sodium hypochlorite immersion disinfection (Group 1A and 2A) 0.3% benzalkonium chloride immersion disinfection (Group 1B and 2B) and 2% Glutaraldehyde(Group 1C and 2C). Ten samples from each impression material served as controls (Group 1D and 2D) in which samples were rinsed under tap water for 10 seconds. The surface texture was measured by surface profilometer and dimensional accuracy by digital vernier calliper.
Results: Statistical analysis of computed data was carried by ANOVA and Chi square test. Results of the present study indicate that siloxane impression materials were quite smooth and dimensionally accurate than the polyether impression materials. All the disfectants tested lead to change in surface topography and dimensional changes in both impression materials but the changes are statistically insignificant.
Conclusion: The results demonstrated that the addition silicone and polyether impressions could be disinfected by immersion disinfectants without change in their surface topography and dimensional accuracy.
Keywords: benzalkonium chloride, Glutaraldehyde