Over-Denture (OVD)

All too often we hear the following story from our patients.

    "I had bad teeth; and the dentist said he couldn't save them, so I had all of them pulled."

Unfortunately, this treatment decision is the beginning of a long downward spiral of bone loss, decreased function, collapse of the facial muscles, and loss of confidence and self esteem. 

"So if my general dentists says I have to have all of my teeth pulled, how can you do anything different than make dentures?"  Great question!  Hopefully, you have read this information before you have committed to extracting all of your teeth. We can help you.  We may even be able to help you keep some or all of your remaining teeth.

We frequently find 2, 3, 4 or more teeth that are "salvageable", i.e they are strategically positioned in the arch, and they have adequate bone support (a minimum of 10mm of bone).  We can use these teeth by reducing them to the gumline, and building the denture over the "short teeth" (overdenture abutments)(Fig. 2 & 4).  This type of denture is called an overdenture (OVD), because it is made "over" the remaining teeth. 

An overdenture looks like a complete denture (CD) (Fig. 1); but unlike a complete denture, not all of the teeth are removed.  The abutment  teeth provide support for the overdenture (Fig. 2 & 4).

In certain instances the overdenture abutment teeth can also be used to provide retention for the overdenture by incorporating precision attachments into the roots (Fig. 6, 7, 8 & 9). 

   

 Fig. 1
     Lower Complete Overdenture. 
It looks like a regular complete denture from the tooth side.

 Fig. 2
    Model of a mouth prepared for and overdenture.  Not that three roots have been retained.  The provide support for the denture and they maintain the bone.

 Fig. 3
   The underside of the overdenture.   If you look closely you will see the three recessed areas where the tooth roots are located

Advantages

1.  Keeping the teeth will help preserve the bone around the teeth (Fig 2 & 4).  This will provide a better
     foundation when a new denture is needed  in 7 to 10 years.
2.  If multiple teeth are retained, this will decrease the bone loss over time, resulting in fewer denture
     relines and the associated expense (Fig. 4).
3.  You can bite 8x to 10x harder with an OVD than with a complete denture, because you are still biting
     on your own teeth.  They just happen to be “short” teeth underneath the denture.
4.  If the overdenture abutment teeth are lost due to decay or gum disease, the teeth can be removed,
     and the overdenture can be relined in the area of the extractions without the need to remake the
     denture.


 

 

 5.  Reducing the  the teeth just above the gumline reduces the tipping forces which can loosen the teeth, especially where there is bone loss due to gum disease (periodontal disease). Even teeth with significant bone loss can be used to support an overdenture for many years.

6.  Precision attachments (Fig. 6,7,8 & 9) can be placed in the supporting teeth to improve the stability and retention of the denture.

 Fig. 4
    This photo is of a mouth prepared for an
upper overdenture on 6 teeth. This is 10
years after the denture was delivered. 
Note how the bone has been maintained.
It has not been necessary to reline the denture because of bone loss.

  7.  Oral hygiene is much easier.  Regular, effective brushing and daily use of a fluoride gel in the denture is all that is required to maintain the teeth for many years.  It is no longer necessary to floss.


   
 Fig. 5
Lower Overdenture retained by precision attachments.  It looks like a conventional complete denture.		  Fig. 6
Two roots have been retained for overdenture support.  Precision attachments have been cemented in the roots to proved retention for the overdenture.

 Fig. 7
Underside of the denture shows the precision attachments that "Snap" into the receptacle that is cemented in the roots (Fig. 5).
Fig. 8
Mouth prepared for a lower
overdenture with precision
attachments.  One precision attachment on the left is cemented in the root of the tooth.  The precision attachment on the left has been cast into a gold coping, due to the previous decay on this root.  Also, note how the bone around the roots has been preserved.

 Fig. 9
Underside of the denture for the mouth in Fig. 8.  Notice the two precision attachments.  They  engage the receptacles that have been cemented in the lower tooth roots for added retention and stability of the lower denture

Disadvantages

1.  The fees for OVDs are more than the fees for conventional complete dentures, because of the
     increased chairtime, lab expense and expertise required to make them.
2.  Root canals are usually required on all the teeth that are to be retained.  This may add significantly   
     to your investment.
3.  The teeth retained for support can still get cavities and gum disease.
4.  The denture will need to be relined, because of bone loss in areas where there are no teeth.
5.  The denture will need to be replaced in 7 to 10 years on average.
6.  Because of the increased biting power, the OVD may crack or break.  Often we recommend a metal
     base or a Targis (space age composite resin matrix) to reinforce an OVD, and reduce the risk of
     fracture.