Disinfectant effect of hydrogen peroxide on impression materials.

Purpose: To evaluate the efficacy of hydrogen peroxide, sodium hypochlorite, and glutaraldehyde in disinfecting dental impression materials; alginate, polyether, condensation silicone and polyvinyl siloxane. The objectives include comparing the microbial reduction (Log R values) and assessing the interaction between microorganisms and disinfectants on these materials.

Methods: Common dental pathogens (Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus hirae, and Streptococcus mutans) were used to contaminate the impression materials. Each contaminated sample was disinfected using hydrogen peroxide, sodium hypochlorite, or glutaraldehyde. Microbial reduction was measured as Log R values. Statistical analyses included Kruskal-Wallis tests and Bonferroni post hoc analyses.

Results: Significant differences in Log R values were observed among the impression materials and disinfectants. Alginate exhibited lower Log R values (4.63 ± 1.56) compared to polyether and polyvinyl siloxane. Sodium hypochlorite showed superior microbial reduction (5.38 ± 0.84) compared to hydrogen peroxide (4.84 ± 1.44). Pseudomonas aeruginosa and Streptococcus mutans had higher Log R values, indicating greater susceptibility to the disinfectants. Glutaraldehyde demonstrated effective microbial reduction (5.51 ± 0.69), with Log R values comparable to sodium hypochlorite (5.38 ± 0.84), making it a potent disinfectant for dental impression materials.

Clinical significance: The study demonstrates that sodium hypochlorite and glutaraldehyde are highly effective in reducing microbial load on dental impression materials. While sodium hypochlorite and glutaraldehyde are recommended for their higher efficacy, hydrogen peroxide offers a safer, less toxic alternative, making it a viable option in specific clinical situations.