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Relieve Irritation With Soft Denture Liners

A soft denture liner is placed in the 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 jawbone is usually thinner than normal and does not resist pressure well. When such tissue is compressed between hard jawbone 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 denture 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 eventually will begin to have increasing problems until a new soft denture liner is placed.

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

If a soft denture liner becomes contaminated with disease-causing microorganisms (a fungus for example), it may not be possible to decontaminate the denture without having to replace the denture 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 buildup in the mouth, this usually results in unacceptable contamination of porous soft denture liners unless meticulous oral hygiene is maintained.

While denture liners generally will last longer than a year, they should 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 jawbone surface. While this helps prevent pain from a moderately unbalanced bite resulting from jawbone shrinkage, it is not a long-term substitute for regular adjustments to balance a denture bite.

Disadvantages of Soft Denture Liners

• Soft denture liners continually deteriorate and collect microorganisms easily; therefore, they generally are 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, soft tissue liners are more expensive than a conventional hard denture liner.

by Joseph J. Massad, D.D.S.

+Jim Du Molin is a leading Internet search expert helping individuals and families connect with the right dentist in their area. Visit his author page.

False Teeth: Porcelain vs. Plastic - Discover The Difference!

In the past, false teeth made with porcelain were generally preferred over false teeth made from plastic due to their greater durability and esthetics. However, in recent years, new generation biomaterials have resulted in the development of very wear-resistant false teeth made from plastic.

Clinically, the esthetics of plastic and porcelain denture teeth is nearly comparable, with good quality false teeth made from porcelain still being the standard for esthetics. However, the majority of dentures today probably are fabricated with false teeth made from plastic. For all practical purposes, the cost of porcelain and false teeth made from plastic are about the same.

While porcelain and plastic teeth are competitive with regards to durability, and to a lesser extent, esthetics and wear, there are other factors that may favor the selection of one type of tooth over another.

Some Selection Factors for False Teeth

Balanced bite and force transmission:

Denture bite (called occlusion) changes due to the constantly changing jawbone (called alveolar bone) upon which a denture rests, and, to varying degrees, uneven tooth wear resulting from use. Unless a denture is evaluated and its occlusion adjusted to a uniform and even contact (called balanced bite or balanced occlusion) at regular intervals, denture occlusion will become unbalanced.

Since false teeth made from porcelain are more wear-resistant, their occlusion will not become significantly self-altered by wear, as will false teeth made from plastic. However, when alveolar bone changes cause an unbalanced occlusion, the resulting biting forces from false teeth made from porcelain will be unevenly transmitted to underlying supporting alveolar bone. Frequent tissue refitting of the denture usually eliminates or lessens this problem.

Porcelain denture teeth tend to transmit the impact of biting forces to the alveolar ridge with greater intensity than that transmitted by plastic teeth in an unbalanced tooth contact situation. Some practitioners are of the opinion that this greater force, especially when uneven as in an unbalanced occlusion, may be damaging to the alveolar ridges and could result in accelerated bone loss.

Therefore, unless denture occlusion is checked and balanced on a regular basis, false teeth made from plastic would probably be a preferred choice over false teeth made from porcelain.

Bone loss:

If a person has lost a great deal of supporting alveolar bone and their gum tissue is not of a sturdy type, then plastic denture teeth might be a better choice. These teeth are more forgiving of excessive forces developing from habits such as clenching, grinding, and tapping or "clacking" of teeth, which seems to be more prevalent among older individuals. Plastic teeth do not transmit forces to underlying bone as intensely as false teeth made from porcelain.

Noise:

If false teeth made from porcelain are vigorously used or sometimes habitually tapped together, a "clacking" sound can be heard. Plastic teeth will muffle this sound and be quiet during normal function or habit jaw motions (called parafunction).

Which Type of Tooth Is Best?

If a person has been successfully wearing dentures with false teeth made from porcelain, then they should probably continue with false teeth made from porcelain. These teeth will not wear as fast as false teeth made from plastic, and the relationship between upper and lower jaws will tend to stay normal for a longer time than with false teeth made from plastic.

Regardless of which type of tooth is selected, the success of the selection is strongly based upon regularly checking dentures for proper balanced occlusion and fit on regular intervals.

If a denture is going to be worn against opposing natural teeth, then false teeth made from plastic should be selected because false teeth made from porcelain, being harder, could excessively wear natural teeth away.

After a thorough examination and frank discussion of what a person wants from wearing a denture, a licensed dentist can effectively discuss which type of tooth would best meet a particular individual's unique needs and desires.

Tooth Strength

Because false teeth made from porcelain are extremely hard in comparison to false teeth made from plastic, they tend to chip and crack more easily. For this reason, when dentures having false teeth made from porcelain are brushed and cleaned, they are generally handled over a sink filled with water or over a towel. Should the denture accidentally fall, the water or towel would help break the fall and hopefully reduce tooth breakage.

by Joseph J. Massad, D.D.S.

+Jim Du Molin is a leading Internet search expert helping individuals and families connect with the right dentist in their area. Visit his author page.