Effect of triclosan dentifrice on toothbrush contamination

The objective of this study was to evaluate by culture and scanning electron microscopy (SEM) the contamination of toothbrushes of 30 children (5-7 years old) by mutans streptococci (MS) when dentifrices with or without triclosan are used.

The clinical procedures were divided into 3 phases at 1-week intervals. In phase 1 (group I), the children brushed their teeth without dentifrice for 4 minutes; phase 2 (group II) brushed with fluoridated dentifrice (Tandy); phase 3 (group III) brushed with dentifrice containing triclosan (Colgate Total). The toothbrushes were then submitted to microbiological processing for the counting of colony-forming units (CFUs) of MS adhered to the bristles. Four toothbrushes from each group were analyzed by SEM.

MS were present on 93% of group I toothbrush bristles and on 77% of group II toothbrush bristles. Only 40% of group III toothbrushes were contaminated with MS. When there was a positive microbiological culture, the formation of cariogenic bacterial biofilm adhered to the bristles of all groups was identified by SEM.

Toothbrush bristles were contaminated by MS after only one use. A dentifrice containing triclosan significantly reduced bacterial contamination of these toothbrushes.