There are three layers of the tooth: enamel (the top layer), dentin (middle layer) and nerve tissue (deepest layer). If your tooth has a cavity in the enamel or dentin layer, a simple filling is enough to repair the cavity. However, if the cavity is left untreated, it will reach the deepest layer of the tooth, the nerve tissue. At this point, a root canal is necessary to repair the tooth. If an infected tooth is left untreated, the infection can get into the bloodstream making your child sick.
If you have a cavity that has reached the nerve tissue, you may experience some or all of the following symptoms: