Crown Dental - in Your Local Area

When Should a Denture Be Replaced?

There is no specifically agreed-upon chronological answer by dentists to "When should a denture be replaced?" There are instances where dentures have been replaced after 1 year or less, and on the opposite side of the spectrum, there are people who have worn the same dentures for 25 or more years. These ranges obviously are extremes.

However, on average, dentists seem to be replacing dentures somewhere between four to eight years. This would seem to imply that the average denture fabricated from contemporary biomaterials will wear out and deteriorate within that time and/or the average denture patient's jaws have changed so much that a new denture must be redone.

Each individual's denture needs are different. There are some factors that a licensed dentist takes into consideration when evaluating the need to replace dentures.

Denture Longevity Considerations

Lost vertical dimension:

The proper linear distance relationship between the upper and lower jaws is called vertical dimension. This is unique for each individual.

As one's jaw changes and the ridges upon which dentures rest shrink, a denture becomes loose and vertical dimension begins to change (the vertical dimension is said to be lost by a certain linear measurement unit such as millimeters). Additional plastic (acrylic resin) is added to the inside of a loosening denture (called relining a denture) to stabilize it by reducing looseness caused from jaw shrinkage. However, relining does not restore vertical dimension in an accurate way.

The current position held by most dentists is that when vertical dimension has been lost by three millimeters or more, a new denture should be fabricated in order to restore vertical dimension and maintain functional health.

There are individuals who have worn the same denture for extended periods with considerable loss of vertical dimension over time. Since vertical dimension loss is a slow, but nevertheless progressive, process, they have gradually adapted to a continually increasing closed bite position. These individuals often have a sunken facial appearance and usually appear much older than their chronological age.

Functioning with an abnormal vertical dimension may eventually result in alterations of the temporomandibular joints (TMJ, the jaw joint located in front of the ears). This can lead to significant pain and difficulty with effective eating and even the jaw motions involved with speech. It frequently becomes quite difficult, if not impossible, to restore such individual's proper vertical dimension and chewing efficiency by relining and repairing this older denture.

Tooth wear:

Aside from impaired ability to chew effectively, excess tooth wear will adversely affect esthetics and cause other problems associated with lost vertical dimension, as described above. While porcelain denture teeth will wear at a slower rate than plastic teeth, they nevertheless will wear and are more susceptible to chipping and cracking. Multiple cracked teeth will need to be replaced.

Deterioration: While the biomaterials used by dentists to fabricate dentures today are quite durable, they still deteriorate and exhibit dimensional change over time -- no longer fitting properly, even after relining.

Aging plastic looses its natural appearance and texture, and coloration fades, making dentures look quite artificial.

Deteriorating plastic also makes it easier for dentures to become excessively contaminated with microorganisms. This contributes to mouth irritation and bad taste, and socially unacceptable odors will develop that no amount of denture cleaning will seem to eliminate.

Keeping regular dental check-ups with your dentist so that one's dentures, soft tissues, and jawbone may be checked is essential to extending the life of a denture and maintaining oral health.

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.

Conventional Removable Partial Dentures

A partial denture is useful for a person missing some teeth, but who still has a number of natural teeth.

This device also is called a removable prosthesis, and is a means by which artificial replacement teeth are held in the mouth. The prosthesis commonly is kept in place by means of clasps. These are thin finger-like structures, usually made of a special resilient metal alloy or sometimes plastic, that rest upon and wrap around some remaining natural teeth. Clasps keep the prosthesis securely in place, but still allow a person to easily take it out for regular cleaning and proper brushing of remaining natural teeth.

Some Reasons for Having Partial Dentures Made

• Replace missing teeth
• Improve ability to chew more naturally
• Chew food with confidence
• Make it possible to eat certain favorite foods
• Maintain a healthier and socially acceptable mouth
• Aid in the preservation of remaining natural teeth
• Help prevent or treat problems of the TMJ (the jaw joint)
• Often improve speech
• Help develop a more pleasing and confident smile
• Support the face -- often with a more youthful appearance
• Enhance self esteem
• Replace missing teeth in an economical way
• Add an additional tooth to an existing partial denture if a natural tooth is lost
• In most cases, crowning teeth is not necessary to fit a partial denture
• Partial dentures are usually easy to repair if they are broken

Esthetics and the Conventional Partial Denture

Generally, clasp design is reasonably esthetic, and often it is possible for them not to be seen. However, depending upon partial denture design, which is based on mouth conditions, there may be some show of clasps. Often, this is not an appearance problem. However, if avoiding an unacceptable show of clasps would compromise optimal partial denture design, various special attachments sometimes may be employed to do away with conventional clasps. These attachments are more technically complex and often are referred to as precision or semi-precision attachments.

How Long Will a Partial Denture Last?

Accidents happen, and the mouth is constantly changing. Partial dentures may no longer fit properly, can break or bend, or simply wear out. In fact, there is nothing made for the mouth that is permanent. Fractured clasps and so forth often may be repaired.

On average, a partial denture may be expected to last about five years. Depending upon circumstances, certain removable prostheses can last a shorter or longer time.

How Often Should a Partial Denture Be Checked?

It is best to have a partial denture, as well as the rest of the mouth, checked at six-month intervals. If left uncorrected, small problems can develop into major ones, which could cause disease, loss of teeth, or necessitate premature prosthesis replacement.

Partial Dentures Need to Be Relined

The jaw ridge that a partial denture rests upon is constantly changing. It is normal and necessary to regularly modify how a partial denture contacts the ridge. This maintenance correction is called relining, and on average, needs to be performed annually for optimal function. However, this is dependent upon how an individual's mouth changes. A licensed dentist can best advise when a reline is needed, and when a reline will no longer adequately restore proper function.

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.