If you have never had a cavity, congratulations! If you have had one, you are not alone. About 78% of us have had at least one cavity by the time we reach age 17, according to a 2000 report by the U.S. Surgeon General. Fortunately there's a time-tested treatment for cavities: the dental filling.
Fillings do just what the name implies — seal a small hole in your tooth, i.e., a cavity, caused by decay. This prevents the decay (a bacteria-induced infection) from spreading further into your tooth and, if untreated, continue on to the sensitive inner pulp (nerve) tissue located in the root canal. Should that happen, you would need root canal treatment