Our enemy, in the fight against cavities, is plaque. Plaque is a sticky film of food and bacteria that forms constantly on your teeth. Thousands of bacteria exist in everyone's mouth, and most of these bacteria are beneficial. But, there are two types of bacteria that are the primary culprits in the tooth decay process. The bacteria in plaque thrive on sugar, and produce acid as a byproduct when they break down the sugar. Every time you eat a starchy food like crackers, bread, cookies or candy, the acid is attacking your teeth for 20 minutes or more. Foods that stick to your teeth like potato chips, dried fruit, hard candies and granola bars give the acids more time to work on destroying your tooth. The more frequently you eat, the more your teeth are exposed to these acids. Like all acids, the acid produced by the bacteria in your mouth is corrosive, which means that it dissolves other materials. Your teeth are the victims of this corrosive action. The acid wears away at them, eventually creating holes in the outer layer of your teeth, which are known as cavities.
The acid slowly dissolves the hard, protective enamel layer on your teeth, forming a demineralized area that appears as a white or brown spot on your tooth. That spot is the first sign of tooth decay. If the area does not remineralize, it will progress until a hole develops on the surface of your tooth. Cavities first form in the enamel layer of your teeth. Beneath the enamel is a softer layer called the dentin. If a cavity dissolves through the enamel and reaches the dentin, it can grow much more quickly and threaten the inner layer of the tooth, containing its nerves and blood vessels. If the decay is allowed to reach this level it is likely that root canal treatment will need to be performed. That's why regular checkups and cleanings are very important. If a cavity is found, it can be restored while the cavity is still small and isolated in the outer enamel layer.
To repair a tooth with a cavity, the decayed portion of the tooth is removed and replaced with a filling, provided the damage is not extensive and there is still plenty of healthy tooth structure remaining. However, preventing decay is the preferred solution.
