A soft liner is placed in that part of a denture base that contacts tissues. This provides comfort for those persons experiencing considerable pain while wearing a denture that has a hard plastic interface (the inside of the denture).

These individuals may have a low threshold for pain, and/or the gum tissue that overlays jaw bone is usually thinner than normal and does not resist pressure well. When such tissue is compressed between hard jaw bone and hard denture plastic, pain is easily elicited. Replacing one of these hard interfaces with a soft denture liner helps eliminate or reduce this painful tissue compression.

Some characteristics of soft denture liners

Denture liners are usually fabricated from special medical grade rubber or silicone type compounds. The silicone materials are generally more compressible and consequently softer.

In order for these materials to function adequately they must be reasonably thick. Therefore, the amount of plastic that needs to be removed from the inside of a denture, to allow room for these liners, may weaken some dentures. In those cases it becomes necessary to incorporate a reinforcing metal framework within the body of certain dentures. There are several steps involved in installing a soft liner, such as impressions and various laboratory procedures.

Soft denture liners tend to continually harden, though a patient may not be aware of this happening because the process is gradual. However, they will eventually begin to have increasing problems until a new soft liner is placed.

Denture liners are porous in nature with accounts for why they are soft. However, this porosity contributes to their deterioration and collection of microorganisms.

If a soft denture liner become contaminated with disease causing microorganisms (a fungus for example), it may not be possible to decontaminate the denture without having to replace the liner.

Persons with dry mouth usually have difficulty wearing dentures due to pain and irritation caused by the hard denture surface rubbing against underlying tissues that are not lubricated with adequate saliva. While soft denture liners would appear to be ideal for such individuals, they are generally much more difficult to maintain. Because impaired saliva production allows a very significant collection of microorganisms to build-up in the mouth, this usually results in unacceptable contamination of porous soft denture liners unless meticulous hygiene is maintained.

While denture liners will generally last longer than a year, they should be considered to be replaced on an annual basis or sooner. The frequency of replacement depends on each situation and the patient's oral hygiene.

Advantages of soft denture liners

A gentle and kinder denture interface for those individuals with sensitive underlying tissues.

The soft denture liner tends to compress and conform to a constantly changing jaw bone surface. While this helps prevent pain from a moderately unbalanced bite resulting from jaw bone shrinkage, it is not a long-term substitute for regular adjustments to balance a denture bite.

Disadvantages of soft tissue liners Soft denture liners continually deteriorate and collect microorganisms easily; therefore, they are generally replaced on an annual basis.

Because soft denture liners help reduce pain from an uneven bite, patients may get a false sense of security - - thinking their denture is adequately functioning while the bite continues to deteriorate. Routine dental check-ups are a necessity.

Generally more expensive than a conventional hard denture liner.