Question

How to toothpaste prevent tooth decay?

Answer 1

Fluoride is a very safe and effective way to help prevent tooth decay, so is an important ingredient in toothpaste and mouthwashes. It works by making the enamel (that's the tooth's hard outer surface) more resistant to acids produced by the bacteria living on the teeth and gums.

Answer 2

When we sleep and get up in in morning there is acid present in our mouth which can cause cavity but toothpaste contain calcium fluorides which is a base and it reacts with acid present in our mouth and neutrilize it thus preventing cavities....
Hope this helps you.....