India, Oct. 17 -- The quest for minty-fresh breath goes back at least 5,000 years.

Around 3000 BCE, Ancient Egyptians equated beauty and health with a good set of teeth. They mixed ground-up oxen hooves, pumice and water to make what was likely the world's first toothpaste. (Dentists still use a form of pumice to polish tooth enamel.)

Across the ancient world, other cultures devised their own methods. Indians used dantakastha or teeth-cleaning twigs from the neem, babul or mango tree (many Indians still do). The Chinese used a powder made primarily of fish bones. The Ancient Greeks and Romans used a mix of crushed-up bones and oyster shell.

In pre-industrialised Europe, homemade toothpaste from the neighbourhood apothecary was one of t...