Overdenture

Complete dentures cover your entire jaw, either upper or lower. Some people refer to them as "plates". Complete dentures rest directly on the gum that covers the bone. However, a type of full denture, called an overdenture, fits over a few remaining teeth that have been shaped  and protected by your dentist.

Maintaining a few natural teeth and replacing the missing teeth with an overdenture has several advantages:

• Your natural teeth help preserve bone.
• Your remaining natural teeth bear some of the chewing pressure, which reduces pressure on other areas of the jaw.
• Your remaining teeth improve the stability of the denture and make it less likely to shift in your mouth.
• Your sense of where your jaw is in space and the pressure you are placing on the denture is better than the sense you have after losing all of your teeth.
• Keeping some teeth can help you psychologically accept your denture.

An overdenture usually is used in the lower jaw where a few teeth can be maintained, and is an option for many. However, the teeth that will be preserved must meet certain standards of health. Canines and premolars are the most common teeth selected because of their root length and position in the jaw.

The teeth will have to be shaped to fit the denture. Since the shaping may expose the tooth's living pulp, the teeth usually need root canal treatment which removes the pulp and replaces it with filling material. The teeth are covered with thin metal castings called copings, which fit into openings in the denture. Attachments also can be put on the copings so the denture is better retained in the mouth.

Overdentures also can fit over implants instead of natural teeth. In fact, implants originally were developed to give people " artificial roots" on which to place bridges or dentures in the lower jaw. The dentures can fit directly onto the implants, or a metal bar can link implants together, providing support for the denture.