Do You Know What's Living On Your Toothbrush?

Abdulla, Bushra, and Elina Shimiyeva


The purpose of this abstract is to inform dental health professionals about the adherence of bacteria to toothbrushes as well as their replacement and care.


The type of toothbrush and length of time of use affect the adherence of certain types and amount of bacteria. Remnants of bacteria on a toothbrush may pose a threat of recontamination to the oral cavity.  Compromised or otherwise “unhealthy” individuals have a higher chance of reinfection and should replace their toothbrush more often.


When cariogenic microorganisms survive and remain retentive on toothbrushes; it can recontaminate the mouth with the bacteria that lives on the toothbrush.   The longer the  toothbrush is being regularly used, the more prone it is to adherence of bacteria. Some factors that affect the type and adherence of bacteria are the length of use and the type of filaments of the toothbrush.  The types of microorganisms found on toothbrushes after 24 hrs of drying were Streptococcus mutans the primary bacterium causing dental caries, Beta-hemolytic Streptococcus the cause of strep throat, Candida albicans the fungus causing thrush in babies, coliform bacteria which are found in the bathroom, and Herpes simplex virus which comes from cold sores.   The aim of our presentation is to discuss the effects of bacterial adherence on toothbrushes, and exactly what we should be telling our patients as dental professionals regarding toothbrush care.  


The adherence of microorganisms to toothbrushes reinforces the notion that toothbrushes should in fact be replaced every 3-4 months. Toothbrushes have been found to have specific bacteria that may be detrimental to optimal oral health, especially in those who have compromised oral health. However, more studies need to be conducted with different oral environments and toothpastes to see if the antimicrobial properties of toothpastes will make a difference in the presence of bacteria.