A tongue cleaner (also called a tongue scraper or tongue brush) is an oral hygiene device designed to clean the bacterial build-up, food debris, fungi, and dead cells from the surface of the tongue. The bacteria and fungi that grow on the tongue are related to many common oral care and general health problems. In addition, decaying bacteria produce volatile sulphur compounds on the rear of the tongue; these molecules account for 80 to 95 percent of all cases of halitosis (bad breath).