In the United States, although toothbrushes were available at the end of the 19th century, the practice did not become widespread until after the Second World War, when US soldiers continued the tooth brushing that had been required during their military service.
In the United States, while toothbrushes existed by the late 19th century, the habit did not gain popularity until after World War II. During this time, US soldiers maintained the tooth brushing routine they were accustomed to in their military service.