ELI5: Explain Like I'm 5

Sodium monofluorophosphate

Sodium monofluorophosphate is a chemical used in toothpaste and mouth rinse to help prevent tooth decay. It works by releasing fluoride, which helps to strengthen tooth enamel and protect it against plaque. This means that it makes it harder for bacteria to stick to teeth, which helps to keep your teeth healthy and free from cavities.