Question

what is the cause of the toothdecay ? how does the tooth pastes help to protect our teeth

Answer 1

Permanently damaged areas in teeth that develop into tiny holes is the cause of toothdecay. Fluoride is a very safe and effective way to help prevent tooth decay, so is an important ingredient in toothpasteand 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 theteeth and gums.

Answer 2

well the only reason for tooth decay
can be because of eating sugary stuff or not brushing teeth twice a day. Toothpastes helps to protect our tooth because it has some kind of formula that kills the germ that have spreaded over night...
Hope it helped mate
please mark it as brainliest^_^