How many dental implants do I need to get rid of my denture?

This can be a tricky question.  First, I am going to assume that you want a fixed appliance or at least an appliance that gives you the same chewing power as a fixed appliance.  There are many people that do fine with removable dentures (plates), but then there are others, who really suffer with their dentures.  The empirical fact, however is this:  With a very well fitting pair of dentures (and that is very rare !!) a patient can achieve at most about 15% of their original biting power.  As you can imagine, this can severely limit your nutritional intake as well as your food enjoyment.  Dentures typically cover the whole palate.  Well, it just so happens that a great deal of taste buds are located in the palate, which are suddenly excluded from the tasting experience.

Now, in order to restore such a case to full functionality, we need several implants to gain enough bone anchorage in order to get the patient back to about 90% of their original biting force.  At a minimum 8 implants are recommended in the upper jaw and at a minimum 6 implants are recommended in the lower jaw (the bone is generally denser in the lower jaw !).

Additionally, the upper jaw may still need to be somewhat removable for the patient, so that he or she can clean the support structures for the appliance or prosthesis better.  This is not as often the case in the lower jaw.  The reason for this is that there is usually a flange on the lip side of the upper jaw prosthesis (see pictures below) and a little extension on the palatal side, to assure a good phonetic seal.  It is impossible to clean underneath this type of appliance if it was fixed.  We therefore often make “Fixed-Removable” appliances, which give you the same biting power as a completely fixed appliance, but can be removed for cleaning purposes.  Below are a series of images, which illustrate a “Fixed-Removable” appliance for the upper jaw.

X-ray of 8 implants in the upper jaw

X-ray of 8 implants in the upper jaw

Here we see an x-ray image of implants placed into the upper jaw.  We chose 8 implants to give the patient enough support to be able to chew “steaks” again.  In this image one can see that the lower teeth need some extensive work too, but the patient wanted to get started with the upper arch first, because he could not tolerate his denture anymore.

8 implants in the upper jaw with abutments connected

8 implants in the upper jaw with abutments connected

This image shows the implants in the patient’s mouth.  actually what is visible are the abutments, which are connected to the implants.  The implants themselves are buried in the bone and underneath the gum tissues and are therefore not visible.  These abutments, however are custom milled abutments which exhibit a 3-degree taper.  This is necessary, because the appliance will attach to these abutments via simple friction fit.
Fixed-Removable Appliance

Fixed-Removable Appliance

In this image we can see the appliance itself.  As you can see, it has only minimal extensions of acrylic and no palatal coverage.  The amount of pink acrylic necessary will largely depend on the amount of bone and gum tissue loss that has happened prior to the implant placements.  Once teeth are extracted, bone and gum tissue will shrink away.  That is an inevitable fact.  The less tissue loss we have, the less pink acrylic we have to use.
Palatal side of the Fixed-Retrievable appliance

Palatal side of the Fixed-Retrievable appliance

This image shows the flip side ( the palatal side) of the “fixed-retrievable appliance.  You can clearly see that it is metal re-enforced, in order to give it good stability and fracture resistance.  Furthermore, you can appreciate the “golden” metal caps.  These are the “female” friction components to the custom abutments shown above.  The patient will be able to positively seat the appliance without any rocking and will also be able to “wiggle” it back out.  The chewing power the patient gains is similar to that of a completely fixed bridge.  Additionally, the bone and gum tissue resorption has been arrested.  Since the dental implants are bone anchored devices, they transmit enough of a “stimulus to the bone, to maintain itself rather than resorb.
Please keep in mind that this represents only one out of many appliance options that could have been used in this scenario.  The one which is depicted here is a result of what worked best for this particular patient along several parameters.


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