At least 5000 years ago. "Chew sticks" - twigs with frayed ends resembling brushes - have been found in Egyptian tombs from 3000 BC. Babylonian chew sticks, dating from 3500 BC have also been found. These acted like tooth-picks, rather than brushes. The ancient Chinese, Romans and Greeks were also avid practitioners of dental hygiene. The Greeks used fingers and linen sheets to clean their teeth. The first modern bristled toothbrushes were made by William Addis of Clerkenald, England around 1780 and were in general use around Europe and Japan by the early 1800s, with the first toothpastes appearing at around the same time. The first American toothbrushes were patented later that century, although interestingly it took soldiers returning from Europe after World War II to popularise the practice in America. http://www.wholepop.com/features/oral/look_ma.html http://www.toothbrushexpress.com/html/toothbrush_history.html http://www.oralb.com/learningcenter/teaching/history.asp http://www.dentistry4u.com/history_of_dentistry.htm