Bridges are designed to replace one or two missing teeth. Bridges involve cutting next to an empty spot teeth and putting crowns on them to support a fake porcelain or Zirconia tooth in the middle. So, its usually 2, 3, or 4 crowns fused together, with a fake tooth in the middle, and the bridge is hanging on nearby teeth. They fell very natural in the mouth, and often after a while people forget, which tooth was missing. Bridges require care, like everything else, and the best way it is to floss underneath them or use a water pick.