Dentures replace all the natural teeth in the jaw. “Complete Dentures” is the term used to describe both upper and lower full dentures. This means the dentures replace all the teeth in both jaws. Dentures only provide about 30% of the chewing ability of natural teeth.
Because upper and lower dentures are so different, they are best discussed separately.
An upper denture, replacing all the teeth in just the upper jaw, is usually fairly well tolerated by most people. A new denture, especially the first new denture, always takes some accommodation and a period of adjustment. Eventually, most people are comfortable enough that they often forget they have an upper denture at all.
A full lower denture, however, is a completely “different animal” than an upper denture! While an upper denture has “suction” to help hold it in place when eating or speaking, a lower denture does not have any suction. It is held in place by the posture of the checks and tongue. Learning this posture is something like the skill required by people who learn to walk with baskets balanced on their head. Time, patience and practice are the only solution for getting used to a lower full denture.
Because of the frequent problems with lower dentures, dentists always try to preserve some lower natural teeth whenever possible. This makes it possible to construct a partial denture which is much more comfortable and stable because it has the natural teeth as anchors. Dental implants can also be placed in the jaw to stabilize a denture and this is most commonly done for lower dentures.
Just like natural teeth, some “maintenance” of dentures is required. They should be rinsed after every meal and brushed gently with a soft toothbrush twice a day. A special “denture toothbrush” is not really necessary.
Denture wearers should see their dentist once each year for an examination of both the dentures and all the tissue in the mouth. An oral cancer exam should be part of this annual visit. The dentures should also be checked by the dentist for wear, cracks and the fit of the dentures in the mouth.
While the dentures don’t change, the jaw bone and gums continue to change throughout life so the fit of the dentures always changes.
A dentist can sometimes “reline” a denture to improve the fit against the gums. The reline replaces the pink part of the denture that rests on the gums but does not change the teeth in the denture.
The changing jaw and gums can also cause the denture occlusion (the “bite” – the way the upper and lower teeth come together) to change over time. This is something like the alignment of the wheels on your car. But instead of wearing out your tires prematurely, a changed “bite” causes more stress on the underlying jaw bone and gums which causes them to shrink even faster.
A changed bite usually cannot be improved with a denture reline. It often requires that a denture be remade.
A high quality denture carefully made with modern materials and wear-resistant denture teeth should last between five and ten years but may benefit from relining every three to five years.