How a cavity is formed?

A cavity is a hole in a tooth due to the tooth enamel is destroyed or eroded by losing minerals. The cavity is also called tooth decay or dental caries. The cavity can cause pain, sensitive to hot or cold, inflammation of gum, and lose the tooth. It doesn’t matter if you are old or young, male or female, the cavity affects everyone. Once a cavity is developed, the damage to the tooth is permanent. You have to see a dentist to get dental filling to repair the tooth.

What cause the tooth enamel lose minerals?  The culprit is an acid. The acid in your mouth dissolve the minerals of the tooth to cause the cavity.  Bacteria in your mouth turn any foods with carbohydrates to acid. The acid, food debris, bacteria and saliva combine together to form plaque on your teeth.  Over the time, the acid in plaque gradually eats away the tooth enamel, then form a cavity.  

The tooth enamel is composed of around 95% minerals. Most of the minerals is hydroxyapatite (Ca₅(PO₄)₃OH) that formed by calcium and phosphate ions. The acids in your mouth react with the tooth enamel causing the tooth enamel dissolving. Over the time, the cavity is formed. Here is the chemical reaction formula:

Ca₅(PO₄)₃OH(s) (Tooth enamel) + H⁺ (Acid) (aq) → Ca₅(PO₄)₃⁺(aq) + H₂O(l)

Where aq is the abbreviation of “Aqueous” meaning dissolved in solution.

The sequential of the cavity formation is as follow:

Foods with carbohydrates => bacteria => acid => plaque =>cavity

We can target every one of the key item to prevent the cavity. For example, reduce taking the foods and drinks that contain carbohydrates, try not eat or drink too much acidic food or drinks, clean and floss your teeth after meals, use mouth wash to kill bacteria. It is not easier, but you have to try.