An overdenture is a type of denture that is secured by precision dental attachments. The attachments are placed in tooth roots or dental implants, which have been placed specifically for the overdenture attachment.
Types of overdentures include bar joint dentures and telescopic dentures.
If you lose most or all of your lower teeth, there is nothing to hold a denture down while you chew. An overdenture fastens a denture to the jawbone, much in the way natural teeth are anchored. The adjacent teeth may be altered with locking devices or connecting bars to ensure the denture fits properly.
These bar joints support the dentures better than individual implants, though implants are still required to support the bars.
Generally, the more implants, the stronger the bar, and bars on the upper arch always require more implants than bars on the lower arch due to the lesser bone density in the upper jaw.
When patients have compromised bone density due to age or oral disease, a telescopic denture, a type of overdenture system is probably the best option.
The procedure consists of a double crown system, “the telescopic," and involves fitting inner metal crowns and outer crowns on the remaining natural teeth to create a natural looking removable overdenture.
Though this is a reliable denture system that ensures even bite stress distribution, the procedure is extremely complicated and requires root canal therapy for each remaining natural tooth and the insertion of a metal post to ensure the root is strong enough.
Some of the benefits of overdentures include the prevention of bone loss (dental implants actually strengthen the surrounding bone structure), esthetic appeal, improved speech (when compared with other types of dentures), proper jaw alignment, and improved chewing efficiency.