Residues of food and bacteria that accumulate on tooth surfaces form the dental biofilm. When we eat foods rich in sugars, such as cookies or candy, cancer-causing bacteria ferment these sugars and turn them into acids that lower the pH of the oral cavity. When the pH is below 5.5, there is demineralization of the enamel, which, if it persists, is capable of forming microscopic grooves and cracks. If the acidic environment in the mouth persists over time, tooth decay can form.
However, saliva contributes to stopping this attack by coating the teeth and providing calcium and phosphate to replace saliva that has been lost due to demineralization. At this time fluoride becomes most important. The fluoride found in water, toothpastes and mouthwashes, on contact with the surfaces of saliva and teeth, combines with calcium and phosphate and creates a mineral: fluoroapatite. It is much stronger and more resistant than hydroxyapatite, which is a mineral found naturally in enamel and works by protecting teeth from decay.
Therefore, fluoride favors creating an outer layer of stronger enamel that benefits everyone. The sooner you start using fluoride toothpaste, the less likely both children and adults are to develop cavities.
