About two hundred years ago, William Addis invented something that looked more like today’s toothbrush. He took thick animal hairs, called bristles. He attached the hairs to a handle made from animal bone. Addis found that lots of customers wanted his invention.  

People still wanted to improve the tooth cleaner, however. Animal hairs did not feel great against human teeth! Finally, man‐made bristles were created. They were made out of nylon. Then plastic was used for handles. Now toothbrushes could be made quickly and cheaply. Millions were sold.