Over the past twenty years, dental implants have been constantly improving. The science and technology for dental implants now makes implants as predictable and reliable as more traditional dental restorative procedures like crowns and bridges.
Implants are done in two distinct stages. A titanium artificial tooth root is surgically placed into the jaw bone by an oral surgeon, periodontist or general dentist with specialized training. The top of the implant is just below the level of gum tissue and exposed to the inside of the mouth by leaving a small hole in the gums. A “healing cap” is screwed into the threads of the implant to prevent the gum tissue from growing over or into the implant.
A period of 6 weeks to several months is required for the titanium implant to “integrate” with the jaw bone. That means that the bone actually attaches to the implant to provide stability. It should be realized that this attachment is NOT the same as with a natural tooth. There is no periodontal ligament involved, which is the feature in bone to tooth attachment that allows for tooth movement through bone. Implants cannot be moved orthodontically nor be exposed to forces that cause natural teeth to move in response. For this reason, if implants are being considered with multiple missing teeth, your dentist must plan the number of implants and type of restoration placed on the implants carefully.
The type of restoration placed on the implant are varied. In the case of a single tooth, a piece called an abutment is screwed into the implant to replace the healing cap when osseo-integration of the implant has been accomplished. A crown (or cap) is then cemented over the abutment just as if this were a natural tooth that had been prepared for a crown.
There can be several single tooth implants placed either adjacent to one another or in various locations around the mouth where teeth are missing. However, when the span of missing teeth is too great, it becomes more cost effective as well as biologically supportable to place two or three implants and link them together with a fixed bridge. There will be more teeth showing on the bridge than there are implants, just like with traditional bridges on natural teeth. These are also supported be abutments screwed into the implants as with single tooth implants.
When there are many missing teeth (or all of them) implants are usually used to support a removable denture. In these cases, several implants are linked together with a cast metal bar screwed into the implants on short posts. On the under side of the denture clips are inserted which clip onto the bar between the implants. A denture made this way is vastly more comfortable than a traditional denture because it largely rests on the bar instead of the tissue, thus eliminating many of the sore spots caused by dentures. Additionally, the denture is locked into place by the clips and is extremely stable, unlike dentures which tend to slip and shift or come completely out much more easily.
Although implants can be very expensive by comparison with other more traditional dental prosthetics, the potential benefits make them equally valuable. Most patients who have had traditional dental prosthetics replaced by implant supported prosthetics are so happy that they would never go back.