Background: Contaminated toothbrushes may play a role in the transmission of local or systemic diseases. As modern dentistry emphasises prevention and infection control, toothbrushes should be correctly stored, disinfected and changed at regular intervals. Purpose: The aim of this study was to test the efficacy of 3% neem, 2% triclosan, 0.2% chlorhexidine gluconate and 1% sodium hypochlorite as toothbrush disinfectants against Streptococcus mutans. Materials and Methods: This was a double-blind, linear crossover, within-group comparative experimental trial conducted among 40 children aged 12 to 15 years. The study was divided into five phases: (1) distilled water (control); (2) 3% neem; (3) 2% triclosan; (4) 0.2% chlorhexidine gluconate; and (5) 1% sodium hypochlorite. The toothbrushes were collected after 5 days of brushing and were soaked for 12 h in antimicrobial solutions of separate phases, after which the toothbrushes were submitted for microbial analysis to check for the presence of S. mutans. Results: The mean colony-forming units (CFUs) of S. mutans at phase 1 when compared with baseline was not significant (P = 0.17). The other phases had a significant drop in mean CFUs of S. mutans from baseline (P 0. 001). The percentage reduction of mean CFUs of S. mutans from baseline was the highest in phase 2 (86%). Conclusion: It can be concluded that all the solutions are effective in toothbrush decontamination, but 3% neem has greater efficacy than other solutions. Schlagwörter: antimicrobial solutions, contamination, neem, Streptococcus mutans, toothbrush, triclosan