Pages that link here:
Dental floss has a history that his maybe longer than of the toothbrush but we know for sure that it is in use since the 19th century. It is in the wider use since the invention of synthetic materials like nylon.
Since ancient times we had problems with crooked teeth. They interfered with proper eating and were not too aesthetically pleasing. Because of that, we tried to invent mechanical aids that helped us to fix them. Read about history of orthodontics.
Toothbrushes are the most important instrument in maintaining of oral hygiene. At first they were made from primitive materials that grew their own bacteria but today we have toothbrushes that do their job much better.
Except with dentures, missing teeth can be replaced with dental implants. People made and used dental implants since some 4000 years ago, using bamboo pegs and seashells instead of missing teeth.