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Avoiding Conventional Partial Dentures and False Teeth

Precision and semi-precision partial dentures, like conventional partial dentures, replace missing natural teeth with artificial teeth. However, the means by which they are retained in the mouth is different than a conventional clasp prosthesis.

To better understand these partial dentures types, it is best to first review the basics of conventional partial denture clasps.

How Conventional Partial Denture Clasps Function

Most partial dentures are usually kept in place by clasps. These are thin finger-like projections of special resilient metal alloy, or, in certain cases, plastic or plastic-like materials.

• Clasps rest on and around certain remaining natural teeth so that their ends extend into narrow areas below a gentler bulge on the tooth. Sometimes it is necessary to shape a tooth or make a crown for a tooth or teeth in order to develop the right amount and relationship of undercut and bulge for retention.
• When a partial denture is placed in the mouth, clasps gently spring over a tooth bulge and rest in a relaxed state within an undercut.
• A partial dentures are held in place during normal eating, speaking and other activities because clasps resist springing back over tooth bulges.
• Clasp resistance to removal is not great enough to prevent a person from comfortably removing their partial denture whenever they choose.

The Problem With Conventional Denture Clasps

Despite numerous successful conventional clasp designs, they do have some drawbacks.

• Clasps may at times become visible. Often, this is unavoidable and usually is not objectionable. However, for some individuals, the show of clasps is simply not acceptable because of personal circumstances and compromised appearance.
• Certain partial false teeth may function better with retentive means other than conventional clasps.
• Remaining natural tooth structures may be inadequate to accommodat conventional clasps. Therefore, dental crown or crowns may need to be fabricated to correct these deficiencies.

Semi-Precision and Precision Partial Dentures -- Viable Alternatives

Alternatives to conventional clasp partial dentures fall into two categories, both of which have no clasps to show.

• Semi-precision partial dentures are retained in the mouth by means of mechanical interlocking components. A specially-shaped extension of the partial denture fits into or onto a complementary receiving area or projection of a natural tooth that has been crowned.
  The components fit snugly and consist of a semi-rigid metal-to-other-surface interface, which may also be metal or some other resilient material such as nylon.
• Precision partial dentures are similar to the semi-precision type except that the mechanical interlocking components are manufactured to extremely high tolerances and are held together by precise alignment and a rigid metal-to-metal frictional interface of components.

Advantages of Semi-Precision and Precision Partial Dentures

• A cosmetically-enhanced partial denture as compared to conventional partial dentures
• No show of metal clasps
• Blends in with the conformity of remaining natural teeth
• Functions with a more even pressure on remaining natural teeth than conventional partial dentures

Disadvantages of Semi-Precision and Precision Partial Dentures

• Semi-precision partial dentures are the most costly to fabricate
• Usually some natural teeth need to be crowned
• More difficult to fabricate and adjust
• Some components may need periodic replacement

Which Type of Partial Denture Is Best?

Every patient has unique oral health needs that are best determined by a licensed dentist after a thorough examination.

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.

Learn About Conventional Over-Denture

A conventional over-denture rests over some healthy natural tooth roots. This approach was first reported in 1861. To understand this method, it is necessary to review some facts.

An Overview of Alveolar Ridge Dynamics

• Maintaining a denture on the jawbone ridge (called alveolar ridge) is essential to prevent it from becoming loose during eating, speaking, and other activities.
• Preserving the alveolar ridge facilitates denture stability.
• The body tends to conserve energy and nutrients by maintaining only structures with apparent immediate value. A typical example is the bulk reduction of a broken leg held immobile by a full-leg cast for a month or more.
• The body recognizes that the only one purpose for alveolar bone is to hold tooth roots.
• Alveolar bone no longer supporting a tooth root is removed, or literally dissolved away, by the body. This is called resorption, or simply shrinkage.
• Resorption progresses at varying rates in the same person at different times, and at different rates between different people. Resorption progresses rapidly within the first year of losing a tooth, after which time, the rate progresses at a slower pace.

From this overview, if the maximum amount of alveolar ridge is to be maintained, then preserving the maximum number of periodontally healthy tooth roots should achieve that end.

Preserving the Sensation of Having Teeth

Studies demonstrate that even though only roots are preserved, and a denture covers them, a patient still has sensory input sensations similar to that experienced with teeth, as opposed to individuals with conventional dentures and no preserved roots. Over-denture patients also appear to have a more natural perceived directional sense in their chewing activities. In other words, many patients relate that they still feel like they have teeth -- a positive comment.

Underlying Philosophy of the Conventional Over-Denture

If a patient's treatment plan to have a denture, and the roots of some remaining teeth are supported in healthy alveolar bone, then a conventional over-denture is a viable consideration.

However, only a licensed dentist can determine if a conventional over-denture is a suitable consideration for a certain person, after a comprehensive examination.

Some Characteristics of a Conventional Over-Denture

• Most of a tooth crown (that part of the tooth above the gums) is removed. This often necessitates root canal therapy if not already done.
• The remaining tooth, projecting above the gum, is rounded and usually covered with a similarly shaped artificial crown-like covering.
• Various configurations and extensions may be built onto some retained roots. In those cases, that portion of the denture overlying these configurations is modified to contain attachments that clip onto a framework or receive the individual extensions. In addition to preserving alveolar bone and sensory input, the denture is held securely in place, but may be comfortably and easily removed for cleaning.

Advantages of a Conventional Over-Denture

• Feels more like having teeth
• More retentive in many cases
• Helps reduce shrinkage of surrounding bone
• Reduces pressure to portions of the alveolar ridge
• Positive psychological advantage of still having teeth

Disadvantages of a Conventional Over-Denture

• Scrupulous oral hygiene is essential in order to prevent decay and gum disease
• The over-denture may feel bulkier than a conventional denture
• Frequent maintenance examinations are necessary
• Generally, this is a more expensive approach than a conventional denture

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.