Are Lower Dentures Always A Problem?
While dentures are marginally adequate substitutes for missing natural teeth, the lower denture can be troublesome for many individuals.
Inherent Lower Denture Problems
- A lower denture interfaces with more movable mouth surfaces than an upper denture.
- The lower denture has less stabilizing surface to rest upon. For example, there is no broad palatal surface (roof of the mouth) as in an upper denture.
- Loss of jawbone over time brings a lower denture into closer contact with tissue extensions called frenum attachments, which create dislodging forces.
While these problems are inherent to lower dentures, every person is different and not affected in the same way. There are ways to approach these problems.
Some Considerations for Improving Lower Denture Stability
A thin band-like tissue extension (called a frenum) may attach between a jaw ridge (called an alveolar ridge) and the inside of the cheek. This strip of tissue may become active while eating or speaking and can lift a denture from its alveolar ridge. This frenum attachment may be surgically moved (this is called a frenectomy).
Alveolar ridge bone profile lessens or literally comes closer to the floor of the mouth as jawbone is lost over time. The bone loss is called resorption. This reduces the vestibule or space between the lip and alveolar ridge. Surgical extension of this vestibule (called vestibuloplasty) provides more alveolar ridge exposure for a denture to rest upon and reduces muscle pull due to a high frenum attachment.
As an alveolar ridge loses bone, it often may be built-up by surgically placing various substances beneath the gum tissue to increase both bulk and height of the ridge. This is called alveolar ridge augmentation.
As a person eats and speaks, the lips and cheeks exert forces towards the inside of the mouth while the tongue exerts an outward counter force. There is a space between the tongue and lips and cheeks, called the neutral zone, where there are balanced forces during function. These opposing forces can help maintain a denture in place, with surprising power, if the denture is fabricated so that its bulk and teeth rest within this space.
Inserting metal implants into the jawbone and fabricating a lower denture to receive and connect with these implants in various ways will help stabilize a lower denture, while still allowing for comfortable and easy removal of the prosthesis for cleaning.
Ensuring that upper and lower teeth contact optimally during function (called balanced occlusion) is a basic means of stabilizing a lower denture. If one tooth strikes on one side only, the denture will rock. Even contact or biting is a necessity. Fabrication of a denture that completely avoids contact with all potentially dislodging structures and has a metal base for strength and some weight often will facilitate stability.
What's the Best Approach?
Frequently, several approaches are combined, and not all may be suitable for a particular patient. After a thorough examination, a licensed dentist can best advise an individual as to the best means of helping stabilize a lower denture in their unique situation.
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.
What To Expect From Immediate Dentures
Immediate dentures are placed in the mouth directly after the remaining teeth are extracted. This approach is utilized when a person does not want to be without any teeth for several months while extraction tooth sockets heal and a denture is fabricated.
Immediate Dentures Involve a Two-Step Denture Process
Optimally, immediate dentures are the first denture of a two-denture process and should be considered as a temporary interim prosthesis until a second refined and esthetically enhanced denture may be constructed after healing.
First Stage
- Usually, most or all of the back teeth are removed and extraction sites are allowed to heal for a minimum of six weeks or more, depending upon an individual's healing rate.
- After adequate healing, the immediate dentures unit is fabricated.
- The remaining teeth are extracted and the immediate dentures are placed in the mouth. Wearing immediate dentures right away over extractions normally is no more uncomfortable than the extractions alone.
- Discomfort is managed with proper anesthesia and pain medication. Immediate dentures act like a Band Aid bandage, holding tissues together and protecting them during healing.
- Generally, the dentist does not remove immediate dentures until the day after surgery. Surgery is checked and denture adjustments are made as necessary.
- Immediate dentures will gradually become loose because of bone shrinkage as the jaw continues to heal. Provisional liners are placed in the loosening denture to help hold it in place during healing.
- Adhesives also maintain the denture in place as it becomes looser. If immediate dentures become too loose during this healing period of several months, it may be necessary to reline multiple times.
Second Stage
- After adequate healing has occurred, a second refined denture is fabricated. This denture allows the dentist to artistically position teeth in an optimal and enhanced esthetic relationship, which was not possible with immediate dentures. It also is now possible to establish better functional relationships of the jaws.
- Approximately six months after the second denture is delivered, it will most likely need to be relined to compensate for continuing jaw shrinkage. After this reline, a patient usually needs annual relines to accommodate a continually shrinking jaw.
- The frequency of relines is an individual matter unique to each patient and is best determined by a licensed dentist after a thorough periodic examination that should occur at six-month intervals.
Modified Approaches to Immediate Dentures
- It is possible to extract all the back and front teeth at one time and insert immediate dentures. However, such an approach is problematic and generally is discouraged unless the patient has no other alternatives.
- All teeth may be extracted with no interim denture while the jaws heal and a denture is fabricated. This is generally a more economical approach, but an individual would be without teeth for several months.
Advantages of Immediate Dentures
- A person is not without teeth for any extended period of time.
- Immediate dentures act as a bandage while bony tooth sockets are healing after tooth extractions.
Disadvantages of Immediate Dentures
- A second refined and esthetically enhanced denture is necessary soon after the immediate dentures.
- While the cost of immediate dentures is generally about the same as a conventional denture, the second denture needs to be fabricated soon after the immediate denture. Therefore, a person would be experiencing the additional cost of the second denture sooner.
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.