Toothpaste is a paste used, almost always in conjunction with a toothbrush, to clean teeth.
The earliest known reference to a toothpaste is in a manuscript from Egypt in the 4th century A.D., which perscribes a mixture of powdered salt, pepper, mint leaves, and iris flowers. Many early toothpaste formulations were based on urine. However, toothpastes or powders did not come into general use until the 19th century.
In the early 19th century the toothbrush was usually used only with water, but tooth powders soon gained popularity. Most were home made, chalk, pulverized brick, and salt being common ingredients. An 1866 Home Cyclopedia recommended pulverized charcoal, and cautioned that many patented tooth powders then commercially marketed did more harm than good.
By 1900, baking soda made into a paste by adding a small amount of hydrogen peroxide solution was recommended. Pre-mixed toothpastes were first marketed in the 19th century, but did not surpass the popularity of tooth-powder until about the time of the World War I.
Fluoride started to be added to toothpastes in the 1950s.
