Enter Member/Subscriber ID below as it appears on your BlueCross BlueShield of Tennessee ID card. For example, enter ID number ZEC415012018 as * * *
Noun[edit] cavity â(plural cavities) 1  A hole or hollow depression. 2  A hollow area within the body (such as the sinuses). ( dentistry) A soft area in a decayed tooth.
A cavity is the result of bacteria in the mouth, and its reaction to sugars and starches. As bacteria break down the sugars and starches, sticky plaque filled with acids form over the tooth. If left unchecked, plaque can form tartar, which cannot easily be brushed away.