Dear Student
Tooth decay is a process that leads to cavity. Bacteria in our mouth feed on the sugar present in food that we eat and produce acids. These acids can dissolve the minerals present in our tooth enamel by a process known as demineralization which can cause destruction of the tooth enamel resulting in tooth decay.
When the pH of the mouth falls to around 5.5, tooth decay begins. As the acidity in the mouth increases, the acid reacts with the tooth enamel and causes tooth decay.
Tooth decay can be prevented by brushing with toothpastes (which are basic and neutralise the acid formed) regularly and by cleaning the mouth carefully after meals.
Regards