It is becoming more common to replace a missing tooth with a prosthetic tooth that is placed upon and attached to a dental implant. The dental implant serves as the artificial root that integrates with the bone tissue of the mouth. The prosthetic tooth preferably has a size and color that mimics the missing natural tooth. Consequently, the patient has an aesthetically pleasing and structurally sound artificial tooth.
One current surgical protocol by which implants are integrated into the patient involves two stages. In the first stage, the implant is inserted into the jawbone, covered by suturing the overlying gingival tissue, and allowed to osseointegrate for a period of three to six months. Covering the implant with the overlying gingiva minimizes the likelihood of infection around the implant and is believed to guard against disturbances that may slow its rate of osseointegration. The implants used in the two stage protocol are sometimes referred to as “subgingival implants.”
After osseointegration is complete, the second stage is encountered in which the gingiva is again cut open and a gingival healing abutment is placed onto the implant. The overlying gingiva is sutured to allow it to properly heal around the healing abutment. When the healing abutment is removed and the prosthetic tooth is placed on the implant, the gingiva nicely conforms around the prosthetic tooth. It typically takes four to eight weeks, however, before the gingiva is healed. Thus, the overall procedure may take six to ten months.
Another implant surgical protocol requires one stage and uses an implant called a “transgingival implant” or “single-stage implant” that simultaneously promotes osseointegration and healing of the gingiva. This is accomplished by providing an implant that has a portion that integrates with the jawbone and a portion that extends through the overlying gingiva so that the gingiva properly heals therearound. Thus, the four to eight week gingival healing process in the two stage process occurs during the three to six month period of osseointegration. Consequently, the patient is fitted with a prosthesis in a shorter period of time. And, the gingiva is lacerated and sutured one less time compared with two stage systems which reduces the trauma to that region, the discomfort experienced by the patient, and minimizes the overall cost.
After the implant is installed in either the one stage or two stage surgical protocol, the implant is usually fitted with a low profile healing screw that covers the mechanical components (e.g., the threaded bore) at the gingival end of the implant that will later mate with the prosthesis. In other words, the implant does not typically receive a component that transfers forces or loads to the implant immediately after being installed. Of course, this means that the patient has a vacancy at the site where the implant has been installed until the prosthesis is attached to the implant.
To avoid this vacancy and achieve aesthetic results sooner, it has become more popular to provide a temporary prosthesis immediately after implant installation (i.e., “immediate loading”). It is desirable, however, to modify the existing implant designs and surgical protocols to further increase the success rate of implants that are immediately loaded.