Immediate implants are a benefit to both clinician and patient. However, they are more clinically demanding than delayed implants and have a higher failure rate. One advantage to an immediate implant is if a properly designed temporary crown is placed at the time of implant placement, the process can produce ideal gingival esthetics. The drawback to immediate temporization is that they have the highest failure rate and the time required to create and place the temporary crown can take significant chair time. In addition, may surgeons often find it cumbersome to create and place properly designed immediate implant temporaries.
Many clinicians think that there must be a large area of native bone contact for an immediate implant to be successful. However, when using SteinerBio bone graft materials, only a minimal amount of bone contact is required as long as you have primary bone stability. Another problem is immediate implants without bone grafting will result in angular defects which in the past were considered normal, but in time these areas have been shown to be susceptible to periimplantitis. It is believed that a gap of 1 mm or less does not need to be grafted. Yes, these areas will radiographically fill with bone, but bone does not integrate to the implant. It is simple. Any gap will be filled with soft tissue fibroblasts before osteoblasts arrive. The fibroblasts will cover the surface with fibrous collagen that block integration. The result is there is no bone support in the exact area where it is most needed, and again more susceptible to periimplantitis.
Today, the most common method of treating the defects between bone and implant is to place cadaver bone grafts. But again, this area will look good radiographically but it is scientifically established that these areas do not integrate to the implant surface. It has been shown that immediate implants grafted with cadaver bone break down continually over the years, developing progressively worse angular defects. The following graph is from a study comparing implants that required grafting and implants placed in bone with no coronal defects:
Perfecting Immediate Implants
Immediate implants are also placed, grafted, and covered with a membrane. This method has two draw backs. First, when an implant is covered with a membrane, the gingiva collapses during the integration period producing unacceptable gingival esthetics. However, another complication is when the buccal bone is thin, the action of tooth removal and raising a gingival flap results in resorption of the buccal wall during the integration phase. A thin buccal wall is cortical bone with no cancellous bone. The thin cortical buccal bone receives its blood supply from the periodontal ligament and the gingiva. When you remove the tooth and remove the buccal gingival, the vascular supply to the buccal bone has also been removed. The buccal bone becomes necrotic and is resorbed producing recession and an esthetic defect.
The goal is to produce ideal immediate implants with 100% of the implant surfaces covered with bone that is fully integrated. It is necessary to preserve all the alveolar bone and gingival structures for ideal esthetics. Lastly, the success rates of immediate implants need to equal the success rate of delayed implants and the procedure needs to be simple and cost effective to perform. Let’s take a look at how to accomplish these goals.
In this case, the clinical crown was lost and much of the papilla has resorbed, but the gingival margin is intact.
Pre-op
The first step is to remove the tooth atraumatically with minimal forces being applied to the bone. The tooth is sectioned buccal and lingual, but because the crown is lost and caries are present, it is difficult to show the bur cut into the root. After the root is sectioned, an elevator is used to fracture the mesial and distal portions of the root into two pieces.
After sectioning and fracturing the root into two pieces, periotomes or a bayonet elevator is used to collapse the two pieces of the root into the center of the socket. At this stage, the periodontal ligament has been separated from the root and bone. Loose pieces are removed with mosquito forceps.
The remainder of the root is now easily removed with extraction forceps. A thin buccal wall can withstand significant lateral forces, but vertical forces will fracture and likely destroy the buccal plate. In this procedure, once the buccal and lingual cut is made into the root, the root pieces can then be collapsed into that space using only lateral forces. Because there was no infection or granulation tissue, the socket wall should not be touched to preserve the regenerative cells present in the remaining periodontal ligament. Nothing but sterile saline should be used in the socket.
After preparation of the implant osteotomy, the socket is filled with BioDensification.
When the implant is placed, BioDensification will fill all voids between the implant and socket wall. BioDensification bonds to the implant surface and acts as a bridge for regenerative cells to migrate from the remaining periodontal ligament and bone to the implant surface. Because only migratory cells can enter into BioDensification, bone forming cells enter but nonmigratory cells such as fibroblasts cannot enter, thereby producing bone to implant integration.
Excess BioDensification is evacuated from the socket and a cover screw is placed. Immediate Graft, which is composed of our putty mixed with small perio-size βTCP granules, is gently packed into the defects around the collar of the implant so as to not compress the remaining periodontal ligament.
Filling the defects is complete between the bone and implant and the cover screw is exposed. The cover screw is only used to prevent graft material from filling the internal threads of the implant.
The cover screw is removed and the healing abutment is placed level with the gingival margin. However, as indicated in the photo, there are spaces between the healing abutment and gingiva which expose the implant and graft material. If left exposed, this would allow bacteria to enter and the possibility of washing out the graft material.
The gingiva is compressed with finger pressure to close the gaps between the healing abutment and gingiva. Oral Bond is applied, creating a hermetically sealed site.
The implant is in place with the body of the implant in contact with bone or BioDensification. The defects in the coronal portion of the implant are filled with Immediate Graft which has the ability to maintain space, prevent the buccal wall from collapsing, and resist the ingrowth of fibroblasts facilitating integration around the collar of the implant. Oral Bond provides a hermetic seal and maintains contact between the gingiva and healing abutment which prevents recession.
Post-op radiograph shows all defects filled.
2-week post op shows the graft material is retained and mineralization is occurring.
This procedure will produce 100% bone to implant integration and the presence of the healing abutment bonded to the gingiva will maintain the gingival margin for excellent gingival esthetics. Below yo will see the final results.
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