Crowns and most bridges are fixed prosthetic devices used to strengthen your jaw and teeth. Unlike removable devices such as dentures, which you can take out and clean daily, crowns and bridges are cemented onto existing teeth or implants, and can only be removed by a dentist.
A typical crown "caps" or covers a damaged or diseased tooth. It protects the inside tooth from further damage, as well as improving overall appearance. It looks and acts just like your healthy tooth did before it was damaged. Porcelain or ceramic crowns are popular because they can match the color of your other teeth.
A bridge may be recommended if you're missing one or more teeth. These gaps eventually cause the remaining teeth to rotate or shift into the empty spaces, resulting in a bad bite. This can also lead to gum disease and temporomandibular joint (TMJ) disorders. As with crowns, you have a choice of materials for bridges. Your dentist can help you decide which to use, based on the location and function of the missing tooth (or teeth), aesthetic considerations and cost.