Sharing toothbrushes once is not a big problem, but it is recommended not to do so often, because there are a lot of bacteria and viruses in the mouth, and these microorganisms can be transmitted through saliva and blood. If one person uses a toothbrush, the bacteria and viruses on the toothbrush will remain on the toothbrush. If another person uses the same toothbrush, they may be infected with these microorganisms.
In addition, if a person suffers from oral diseases, such as caries, periodontitis, etc., sharing a toothbrush may aggravate the symptoms of the disease, or even infect other people. Therefore, it is recommended that everyone use their own toothbrush and avoid sharing toothbrushes. If it must be shared, disinfectant or hot water can be used for disinfection.