Posterior Implant Procedures

Posterior Implant Procedures: Replacing Teeth That Are Failing

Teeth supporting a traditional, tooth-supported bridge often fail over time and the bridge must be replaced. The failure can be the result of significant decay, failed root canal therapy, or fracture of one or both of the teeth supporting the bridge. In these situations dental implant treatment is the ideal option for most patients.

There are three steps in the treatment process:

1. Surgical removal of the failed teeth, often with bone grafting to maintain the natural contours of the bone and gum tissue
2. Placement of the dental implants, either immediately after removal of the teeth, or several weeks following tooth removal
3. Attachment of the final implant-supported bridge

Immediate Dental Implant Placement

The first step in the treatment process is removal of the failed bridge, followed by a special surgical technique to remove the teeth, while preserving the bone and gum tissue to achieve the ideal esthetic result. Since any damage to the bone could cause an unsatisfactory result, this procedure is usually performed by surgical specialists with extensive experience removing teeth in preparation for dental implants.

Immediately after the tooth is removed, dental implants are placed using a delicate surgical technique to avoid damaging the bone. The dental implants must be placed so that they are stable and this usually requires affixing them to the bone at the very tip of each tooth socket. Bone grafting material is often placed around the implants, filling in the sockets completely to maintain natural contours.

The position of the dental implants is critical to ensure that the new crowns or bridge emerge from the gum tissue exactly like natural teeth. Due to the precision required for this procedure, the surgical specialist must be experienced with immediate implant placement to ensure a successful outcome.

If esthetics are an issue, a provisional (temporary) removable partial denture can be placed following implant placement. The provisional replacement teeth are primarily for esthetic purposes, rather than function. They are placed so that they do not touch the teeth opposite them to keep the forces of biting off of the dental implants, allowing the bone to remodel around the implants without movement or pressure. Even gentle biting force, causing minor movement, can prevent the bone from fusing to the dental implants. Once the bone has formed a strong bond with the dental implants, providing a stable foundation, the final bridge can be attached to the implants.

Delayed Dental Implant Placement

In cases where there is insufficient bone to stabilize the dental implants immediately following removal of the failed teeth, the surgical specialist could determine that it would be better to delay implant placement. It might also be necessary to place a bone graft following tooth removal, to fill in the sockets where the tooth roots are missing, creating a more ideal site for implant placement.

The bone graft allows the surgical specialist to place the dental implants in bone that provides stronger initial stabilization of the dental implants. After the dental implants are placed, if esthetics are a concern, a provisional (temporary) partial denture is placed so that it does not touch the teeth in the opposite jaw, avoiding biting forces that can cause movement of the dental implants.

The dental implants are left undisturbed for several weeks, or a few months, so that the bone can remodel around, or fuse to the dental implants. Following the appropriate period of time, as determined by the surgical specialist, a small connector post called an abutment is attached to each of the dental implants. The final crowns or bridge will be attached to these abutments.

Replacing Teeth That Are Already Missing

In cases where the teeth have been missing for an extended period of time, the surgical specialist must determine whether there is sufficient bone for placement of dental implants. Both the quality and quantity of bone where the dental implants will be placed must be evaluated. 3D cone beam images with computer-generated scans are often used to facilitate the diagnosis and treatment planning process, as they provide a more detailed look at the existing teeth, bone, nerves, and tissue with both three-dimensional and cross-sectional views.

If a substantial amount of bone has been lost, bone grafting could be required to create an ideal site for placement of dental implants. One of the challenges with replacement of posterior teeth in the upper jaw is the possibility that the sinuses have dropped down into the space vacated by the roots of the missing teeth. In this case, a special bone grafting procedure is required in order to place dental implants. This involves a delicate procedure to gently lift the floor of the sinus to create more space to pack bone grafting material in order to create an ideal site for the placement of the dental implants.

After a predetermined period of time following the bone grafting procedure, usually a few months, a special surgical technique is used to shape the bone for the precise placement of dental implants. The position of the dental implants is critical to ensure that the crowns emerge from the gum tissue exactly like natural teeth for ideal function and esthetics.

If provisional (temporary) replacement teeth are necessary for esthetic purposes, a removable partial denture is placed so that it does not touch the teeth in the opposite jaw to keep the forces of biting off of the dental implants, allowing the bone to remodel around the implants without movement or pressure.

The dental implants are left undisturbed for several weeks, or a few months, so that the bone can remodel around, or fuse to the dental implants. Once the bone has formed a strong bond with the dental implants, small connector posts called abutments are attached to the dental implants. The final crowns or bridge will be attached to these abutments.