6 year Result of Simultaneous Implant Placement after Sinus Elevation through the Crestal Approach with the Microelevators in the thin Residual Bone Height
A 52-year-old malea heavy smoker
Panoramic view on 2009.2.3. Moderate or severe periodontal disease was observed at #15, 17 and 36. Extraction and implant therapy for these three teeth was planned.
Panoramic view after 6 months. Even though the apical defect had been reduced on #15 and 17 area, there was 2-4mm vertical defect at #16 and 17 sites, and available bone heights at #16 and 17 were about 2-3mm.
Intraoral view of maxillary right area six months after extraction. A slight horizontal defect on the buccal side was observed.
The site of #17 had a severe bone defect and exposure of the sinus through about 1mm residual bone thickness.
The 3.6mm wide S-reamer with 1000-2000 rpm was utilized to drill into the sinus until the sinus wall was opened without membrane tearing. The length of the first stopper was 2mm. Additional 1mm stoppers were used as drilling proceeded. Resolute drilling with confidence is needed without reducing speed because the stoppers prevent the reamer from going into the sinus more than 1mm. Therefore stoppers should be used whenever an S-reamer is used. There may be the feeling of sudden drop into an empty space at the moment of perforation of the inferior floor. The head of the S-reamer can go 1-1.5mm into the sinus without any membrane tearing.
The membrane was originally torn at the #17 site, and the residual bone was thin. So, the membrane was detached with the micromembrane elevator in the SLA kit.
A piece of CollaTape, a kind of spongy collagen membrane, was prepared to close the torn membrane.
It was seem that the collagen membrane covered the torn site so that sinus bone graft was possible through the crystal bony opening.
After bone grafting with the crestal approach, a 5x8mm implant was placed at #16. The amount of remaining bone at the #16 area was about 3mm.
Severe horizontal defect at the #15 area was seen.
Three implants were placed. An implant was placed in the #17 area even though the residual bone was about 0.5mm, and the hole was wide so that delayed placement should have been done. Placement situations: #17-Class III C fixation (D300) with 18 Ncm, #16-Class III CM fixation (D240) with 40 Ncm, #15-Class II CMI fixation (D232) with 40 Ncm. An allograft was inserted on the buccal side after placement of a 1mm spacer for the CTi-mem.
The CTi-mem was fixed on the spacer with a CTi-healing abutment.
Non-submerged transmucosal GBR was applied at #15, whereas the other areas were submerged.
Panoramic view after surgery. More than 10mm of sinus elevation at #17 was observed with the crestal approach.
Four months after the surgery. No exposure of the Ti mesh (CTi- mem) was seen.
The CTi-mem was removed four months after the surgery.
Before the spacer was removed there was mild inflamation at the soft tissue by transmucosal GBR, but bone formation had been well established. Transmucosal GBR is not recommended any more.
Uncover surgery was done, and healing abutments were connected.
Two months later, 3 SCRP abutments were connected.
3-unit PFM FPD (SCRP) was delivered.
Panoramic view with final prosthesis six months after sinus graft and implantations. Note that the #17 area was a success despite it’s residual bone height being only 0.5mm.
3 years after final prosthesis. Severe peri-implantitis occurred at #26, so it was treated and grafted.
At 6 year follow-up, there was little marginal bone loss and the bone level was maintained successfully, particularly the implant at the area of #17. However, periodontitis occurred around the implant of #14