In the morning, amidst a dozen other things I have to do, I brush my teeth with minty toothpaste from a plastic tube. While I dislike the taste, I know it keeps my teeth clean, and free from plaque and cavities, among other things. But what is toothpaste, really, and how does it help clean your teeth?
Egypt is where the earliest toothpaste is noted, most likely made from a rock (in its powdered form) called purnice, and mixed with vinegar. Greeks and Romans added substances like bones and oyster shells. In the 19th century, toothpaste became more popular. It was usually made from chalk, brick, and salt. In the 1900’s, it was replaxced with hydrogen peroxide and baking soda.
Fluoride is a really important part of toothpaste these days. Fluoride strengthens the enamel on your teeth. One site writes, “[Chemists] believe that by a process of remineralisation the fluoride turns into fluoride rich compounds known as apatite. This in turn strengthens the enamel, protecting it from dissolving in acid.” I’m pretty sure this site meant remineralization, and just made a spelling error, as remineralization means to convert to a mineral substance.
Another important part of toothpaste is something known as abrasives, which causes the gritty feeling of toothpaste. Abrasives are used to clean teeth by removing stains, plaque and any excess food particles. Some abrasives used today are hydrated silica, aluminium oxides, and calcium carbonate. Different phosphates of calcium or aluminium are also used.
Surfactants are the last piece within toothpaste that I’ll mention today. This is used to help loosen pieces of food or plaque stuck in your teeth to allow your toothbrush to take it away. One site writes, “The structure of these molecules allows it to attach to the stain at one end and water at the other. This is why these molecules can remove those nasty stains by pulling them away.” One example is sodium lauryl sulphate, which also reduces the possibility of plaque growing.
Without toothpaste, our teeth would not be as healthy as they are today, not to mention how much smellier our breath would be!
So ta ta for now and I hope to see your chemical reaction soon!