Germicidal Activity of Antimicrobials and VIOlight^® Personal Travel Toothbrush Sanitizer

Objectives: To evaluate the antibacterial effect of VIOlight^® Personal Travel Toothbrush Sanitizer on biofilms after exposure of toothbrushes to human saliva compared to original Listerine^® Antiseptic (LA), 3% Hydrogen Peroxide (positive control) and no treatment (negative control).

Methods: Twenty new manual toothbrushes were used. Toothbrush heads were immersed in pooled whole human saliva for ~48 hours at 37° ±1°C to allow bacterial growth and biofilm formation. Brush heads were rinsed under running tap-water for 10sec prior to treatment exposure. The UV toothbrush sanitizer was used for 7 minutes, as recommended. Same exposure time and temperature was followed for the antiseptic(s) (20-25°C). After treatment, all brush heads were rinsed for 10sec with tap-water; a 20sec tap-water rinse was conducted on the brush heads that served as the untreated numbers control. Five replicate brush heads were used for each test group. Heads were placed into 10mL of 2X AOAC Letheen Broth (10-1 dilution), sonicated and vortexed for 10sec, respectively. A 1mL aliquot of 2X AOAC Letheen Broth was used to prepare 10-fold serial dilutions in sterile Peptone Water. Dilutions were plated onto Schaedler Blood Agar and incubated both aerobically and anaerobically at ~35°C for ~48 hours. The log10 cfu/ml data were compared utilizing analysis of variance.

Results: Statistical analysis indicated that 3% Hydrogen Peroxide had significantly (p<0.05) lower counts than LA, VIOlight^® and control for both aerobic and anaerobic bacteria. LA had significantly (p<0.05) lower counts than VIOlight^® and control for both bacteria and VIOlight^® had significantly (p<0.05) lower counts than the control for aerobic bacteria. Conclusion: Bacteria can colonize and proliferate on toothbrush heads and may reach the oral cavity every time the brush is used. 3% Hydrogen Peroxide and LA are most effective in rapidly killing bacteria when compared to VIOlight^®.