Abstract
In recent years, the high predictability of oral implant treatment has been verified through both fundamental and clinical research, and this treatment modality is used ill various bone conditions. However, in the case of maxillary molars, which show failures that cannot be anticipated by anatomical characteristics, and which hold many challenges in implant placement surgery, predictability is poor.
From the clinical cases experienced during the 6 year and 2 month period from the establishment of this hospital in October 1997 to December 2003, we specifically analyzed the surgical techniques and the prognosis of implants placed in the maxillary molar region.
The total number of patients was 138 (22.1/month), on which 166 surgical procedures were performed (26.6/month) and 417 implants placed (5.6/month) . Of the total, implants placed in the maxilla numbered 148, or 35.5% of the total, with 77 of these (right side 43, left side 34) placed in the molar region, and the roughly equivalent remainder placed in the maxillary anterior region.
Examining by the type of surgical procedure, we found that 60 implants, or 78%, were placed using a non-standard surgical procedure, with socket lifts (Bone Added Osteotome Sinus Floor Elevation : BAOSFE) accounting for the majority with 30 cases and 47 implants; sinus lifts with 2 cases and 3 implants; and ridge expansion with 1 case and 2 implants. Standard surgical procedures accounted for the remainder of the total, with 7 cases and 17 implants, or 22% of the procedures. Examining by failure cases, early failures accounted for 5 implants, and late failures for 3 implants. Of these, 2 implants had been placed with standard surgical procedures, and 6 implants with nonstandard surgical procedures. The causes of these failures were further investigated.
For the most commonly performed socket lift procedure (BAOSFE), we observed differences in both low and extremely low maxillary sinuses, as well as changes in hone grafts over a period of time using a CT scanner and herein report on our findings.
