Dentures are the simplest and most cost-effective solution for patients who have no teeth at all. Complete dentures are removable plates, for the lower and upper jaws, supporting a full new complement of teeth. The dentures are fitted specially over your gums and are retained in your mouth similar to the way a suction cup sits on a wall. However, there are some limitations to conventional full dentures. While the upper denture offers great stability and retention, the lower denture has less support and may come loose often requiring you to use your tongue to keep it in place.