To place an implant, there must be an adequate amount of bone to bear the brunt of the bite. In the upper molar area, it is very common to be short of bone for implants since the maxillary sinus is located right above it. Since the bone shrinks once a tooth is removed, it is not unusual to find only a few millimeters of bone remaining. In these cases, a procedure called a sinus lift bone graft is available. In a sinus lift, a flap of gum is retracted from the upper jaw in the molar area, and a small window is cut into the bone being careful to not lacerate the sinus membrane. The sinus membrane is gently “lifted” and a bone graft material is placed in the hollowed out space in between the lower part of the sinus bone and the membrane. The surgical site is closed and allowed to heal undisturbed for a number of months. At this point, the bone will be fully organized and ready for implant placement. A sinus lift procedure has over 90% success rate. The feedback that I have gotten from patients as far as the recovery from the procedure has been very favorable. The technique opens up many more opportunities to restore the upper jaw with implants instead of having to resort to dentures.
For an implant to be successful, there must be adequate bone available for proper placement. Since the bone and gums will shrink away once a tooth is removed, it is not unusual to have a situation where there is an inadequate amount of bone to place an implant. Simple techniques start with socket preservation where the dentist places a bone grafting material in the socket at the time of tooth removal. Even more predictable is placing a membrane over the graft material. This will allow the graft to heal undisturbed and has a very high rate of success. Once the bone height has shrunk, then a block graft needs to be done to give the bone more vertical. A block graft uses a piece of cortical bone that is obtained from another part of the body. Common areas are the mandibular ramus (the part of the jaw bone that lies behind the lower back teeth) or the mental symphysis (part of the chin). Once a block of bone has been harvested, then a flap of gum is peeled back at the donor site and the block is held in place with screws. Since the procedure utilizes bone from the same person, it doesn’t reject the graft. After allowing the area to heal for a few months, then the site will be ready for implant placement.