Why is the surgical procedure a three-step process?
The most widely practiced method of placing dental implants is a “staged surgery” procedure. The first stage consists of surgically burying the implant (which replaces the tooth root) flush with the bone but underneath the gum. This protects the implant from force while it is healing. At the end of this healing period, the implant needs to be surgically exposed by removing some of the overlying gum.
At this second stage, the surgeon checks the implant for its successful integration and connects some form of post which penetrates through the gum into the mouth. This post is called the abutment. Abutments come in many forms and can be stock-manufactured or custom-molded by your dentist and a laboratory. The gum is allowed to heal around the abutment and form a cuff or collar through which the dentist has access to the implant when preparing the final restorative stage of placing the prosthetic tooth or teeth.
Research has shown that it is often possible to place a suitable abutment at the same time as the implant. This has certain limitations but can eliminate the need for a second surgery to expose the implant. However, the implant still requires adequate healing time for the bone to osseointegrate.
The abutments must also be protected from chewing forces during this period to assure effective bony integration and successful healing. Once the implants have had a chance to heal and have been tested for successful integration, the final restorative step takes place. This stage consists of fabricating and connecting the prosthetic teeth to the successfully osseointegrated implants.
What is One-Stage Surgery?
This method employs a non-submerged one-piece implant that has a metal collar designed to protrude through the gum while the bone is healing to the implant. After a suitable healing time, an abutment can be connected to the implant, allowing for fabrication of the crown to replace the missing tooth. Alternatively, a one-stage technique can be achieved by immediate connection of a temporary healing abutment to a two-piece implant that protrudes through the gum in much the same way as a one-piece implant. Both single stage and two-stage implants have similar success rates and you should ask your dentist which systems they use and discuss how one- or two-stage procedures might be appropriate for you.
What is the overall success rate for dental implants?
Despite decades of clinical and scientific research, dental implants do not have a 100% success rate. However, the success rates have improved dramatically since the introduction of dental implant surgery and the dental profession can proudly report success rates well above 90% for most implant patients. Similarly, long-term success rates are in the high 90% range and are likewise improving. When a dental implant has not successfully integrated, it may need to be removed, as it cannot easily be “converted” to osseointegrate. Your dentist will give you best advice about this. A replacement implant can be placed but it may require some months of healing time and possibly bone augmentation (repair by means of grafting). Likewise, if a previously placed implant has lost significant amounts of supporting bone, there are currently no treatments that can predictably restore the lost bone after it has been in function in the mouth.