Plaque, and specifically acid, causes tooth decay. Plaque is a clear and odorless bacteria-laden film that forms on the teeth. The bacteria in plaque interact with the starches and sugars we eat and form an acid. This acid breaks down or de-mineralizes teeth. Our saliva, however, act to help re-mineralize teeth. When the demineralization process is faster than that of remineralization, a cavity forms.
Many steps can be taken to slow down or prevent this breakdown process. Eliminating or drastically reducing your intake of sugars will help greatly in preventing tooth decay. Proper brushing and flossing, and removal of the plaque will also help. And, of course, regular visits to the dentist are critical in detecting cavities early and maintaining a healthy mouth.